Current version

v1.10.4 (stable)


Main page
Archived news
Plugin SDK
Knowledge base
Contact info
Other projects



01 Dec - 31 Dec 2013
01 Oct - 31 Oct 2013
01 Aug - 31 Aug 2013
01 May - 31 May 2013
01 Mar - 31 Mar 2013
01 Feb - 29 Feb 2013
01 Dec - 31 Dec 2012
01 Nov - 30 Nov 2012
01 Oct - 31 Oct 2012
01 Sep - 30 Sep 2012
01 Aug - 31 Aug 2012
01 June - 30 June 2012
01 May - 31 May 2012
01 Apr - 30 Apr 2012
01 Dec - 31 Dec 2011
01 Nov - 30 Nov 2011
01 Oct - 31 Oct 2011
01 Sep - 30 Sep 2011
01 Aug - 31 Aug 2011
01 Jul - 31 Jul 2011
01 June - 30 June 2011
01 May - 31 May 2011
01 Apr - 30 Apr 2011
01 Mar - 31 Mar 2011
01 Feb - 29 Feb 2011
01 Jan - 31 Jan 2011
01 Dec - 31 Dec 2010
01 Nov - 30 Nov 2010
01 Oct - 31 Oct 2010
01 Sep - 30 Sep 2010
01 Aug - 31 Aug 2010
01 Jul - 31 Jul 2010
01 June - 30 June 2010
01 May - 31 May 2010
01 Apr - 30 Apr 2010
01 Mar - 31 Mar 2010
01 Feb - 29 Feb 2010
01 Jan - 31 Jan 2010
01 Dec - 31 Dec 2009
01 Nov - 30 Nov 2009
01 Oct - 31 Oct 2009
01 Sep - 30 Sep 2009
01 Aug - 31 Aug 2009
01 Jul - 31 Jul 2009
01 June - 30 June 2009
01 May - 31 May 2009
01 Apr - 30 Apr 2009
01 Mar - 31 Mar 2009
01 Feb - 29 Feb 2009
01 Jan - 31 Jan 2009
01 Dec - 31 Dec 2008
01 Nov - 30 Nov 2008
01 Oct - 31 Oct 2008
01 Sep - 30 Sep 2008
01 Aug - 31 Aug 2008
01 Jul - 31 Jul 2008
01 June - 30 June 2008
01 May - 31 May 2008
01 Apr - 30 Apr 2008
01 Mar - 31 Mar 2008
01 Feb - 29 Feb 2008
01 Jan - 31 Jan 2008
01 Dec - 31 Dec 2007
01 Nov - 30 Nov 2007
01 Oct - 31 Oct 2007
01 Sep - 30 Sep 2007
01 Aug - 31 Aug 2007
01 Jul - 31 Jul 2007
01 June - 30 June 2007
01 May - 31 May 2007
01 Apr - 30 Apr 2007
01 Mar - 31 Mar 2007
01 Feb - 29 Feb 2007
01 Jan - 31 Jan 2007
01 Dec - 31 Dec 2006
01 Nov - 30 Nov 2006
01 Oct - 31 Oct 2006
01 Sep - 30 Sep 2006
01 Aug - 31 Aug 2006
01 Jul - 31 Jul 2006
01 June - 30 June 2006
01 May - 31 May 2006
01 Apr - 30 Apr 2006
01 Mar - 31 Mar 2006
01 Feb - 29 Feb 2006
01 Jan - 31 Jan 2006
01 Dec - 31 Dec 2005
01 Nov - 30 Nov 2005
01 Oct - 31 Oct 2005
01 Sep - 30 Sep 2005
01 Aug - 31 Aug 2005
01 Jul - 31 Jul 2005
01 June - 30 June 2005
01 May - 31 May 2005
01 Apr - 30 Apr 2005
01 Mar - 31 Mar 2005
01 Feb - 29 Feb 2005
01 Jan - 31 Jan 2005
01 Dec - 31 Dec 2004
01 Nov - 30 Nov 2004
01 Oct - 31 Oct 2004
01 Sep - 30 Sep 2004
01 Aug - 31 Aug 2004


Powered by Pivot  
XML: RSS feed 
XML: Atom feed 

§ Altirra now has a home

My 8-bit Atari computer emulator, Altirra, now has a home. You can find it at the bottom of the nav bar on the left. I finally got around to doing it since I don't frequent AtariAge enough to actually participate much there, so I needed somewhere else to put updates, and this blog isn't a good way to keep a permanent link to tip. I was going to do it via a second blog, but after running in circles trying to configure it, I gave up and just made it a static page. There's a reason I work on client-side software.

Anyway, while I was at it, I threw the release switch on the dev directory and posted a new version, Altirra 1.2. Most of the changes are nitpicky emulation fixes, and not too significant unless you have something that actually cares that changes to VSCROL are checked on cycles 108 and 0 of a scanline. A significant change, however, is that I added 65C816 support. The 6502 was first extended in the 65C02 by the addition of some useful opcodes, and the 65C816 was an even bigger upgrade to handle a 24-bit address space and 16-bit arithmetic. It was used in the SNES and in the Apple II GS, but Atari never released an 8-bit system with anything other than a good old fashioned 6502/6502C, making its addition is a bit whimsical. Apparently some accelerators with 65C816s were made, however, and there is a little bit of software out there. It's a bit buggy, but it can run at least one 65C816-based kernel ROM replacement. I think I can also say, after having implemented it, that the 65816 instruction set was a valiant attempt to make the x86 ISA look good. 8-bit emulation + 8/16-bit acc/mem mode + 8/16-bit indexing mode... what a mess. I think I actually prefer x86 real mode to banks and m/x bits.

The change list is a bit better formatted this time. I'm a bit embarrassed to say that it never occurred to me before that after writing the RTF-based change log window code for VirtualDub -- which is also in Altirra -- that I could have simply copied and pasted its text into here instead of manually word-wrapping the text like I usually do.

Version 1.2 [July 5, 2009]:

features added

  • Debugger: Added memory pane.
  • Debugger: Shift+F11 is now a shortcut for Step Out.
  • Debugger: History window now supports the mouse wheel.
  • GTIA: Added artifacting support.
  • UI: Cursor auto-hides when over display pane.
  • UI: Added window pane layout saving.
  • UI: Basic support for an Atari ST mouse in port 2.
  • UI: Added more keyboard mappings.
  • Simulator: Added initial save state support.
  • Simulator: Added option to pause when not the active application.
  • CPU: Initial 65C02 and 65C816 support.
  • bugs fixed

  • Simulator: Fixed RUNAD handling in executable loader.
  • Simulator: Fixed incorrect TRIG3 cartridge sense on launch.
  • UI: Tweaked aspect ratio constants.
  • UI: Fixed some bugs with pane undocking.
  • ANTIC: Added missing address wrapping (fixes hang loading Bounty Bob).
  • ANTIC: Fixed VSCROL timing to acccommodate more mode line extension tricks.
  • ANTIC: Fixed low bits in NMIST register.
  • POKEY: Tweaked hi-pass to sound better.
  • POKEY: Implemented fast pot scan mode.
  • POKEY: Two-tone serial mode now affects timer 1/2 sound output.
  • Debugger: Breakpoints can now be seen on the active line.
  • Debugger: Fixed early stop when trying to Step Out across a PLA or PLP instruction.
  • Debugger: CPU status traces on single-step use the instruction PC rather than the raw PC.
  • HLE: Fixed black status pane in Pole Position due to incorrect attract mode handling.
  • HLE: Fixed startup path problems that prevented SpartaDOS X from starting.
  • HLE: Screen handler now adjusts user memory limit.
  • HLE: Fixed length return value bug in CIO put characters command.
  • HLE: Control codes now work with S:.
  • Disk: Fixed CIO return codes for H: handler.
  • Cartridge: Cart bank is now reset on cold reset.
  • Cartridge: Fixed banking and recognition problems with MaxFlash 1M cartridge format.
  • CPU: Added option to halt on BRK instructions.
  • GTIA: Fixed nasty bug where P/M collisions got messed up whenever the simulator dropped a frame.
  • GTIA: Fixed behavior of sprites when repositioned during active region.
  • GTIA: Implemented text blink and vertical reflect bits.
  • GTIA: Fixed low bit in PAL register in NTSC mode.
  • Comments

    Comments posted:

    You have a small typo in the Altirra page: "Altirra is designed eith emulation quality in mind"

    Darkstar - 05 07 09 - 09:21

    Page fault. :)

    Phaeron - 05 07 09 - 09:29

    you're a real programmer when your keyboard only has five keys: 0, 1, Ctrl, Alt and Del :D

    Mitch 74 (link) - 06 07 09 - 00:48

    Real programmers touch a screwdriver to the reset pins on the mobo instead of using Ctrl+Alt+Del.

    Phaeron - 06 07 09 - 15:13

    Thank you!!

    With Atari800win Plus now dead I was pleased to see you initial emulator, I know you didn't think about extending it's life but I and the Atari community are very glad you carried on, this is shaping up to be a fantastic emulator and it's already bloody good. Thanks for your time and effort, please keep it going and adding features.

    Mclane - 06 07 09 - 20:56

    Just a quick note, some settings like disk drive enabled, image filter don't save their settings unlike others, is this meant?

    Also Right alt does not free the mouse, hitting the next door Start key does after it brings up the start menu. Lastly, are the artifacting colours correct?

    I seem to remember them being more reds and blues after altering the display list on games like Drol and AE.

    Hope this info helps a bit and thanks again..

    Mclane - 06 07 09 - 22:09

    As anyone with experience with VirtualDub can attest, I frequently forget to save settings. :)

    That having been said, I can't think of a reason not to save those. The disk setting isn't too important, though, because Altirra will automatically enable the disk drive when a disk is bound. I usually just quick-start a disk via File > Open since I rarely need more than one disk.

    Right-alt works for me, obviously, but I do my main development in Windows XP. I need to try Windows 7 since someone mentioned full-screen problems there. As you discovered, it'll auto-disengage if the window loses focus, too. The behavior is modeled after Virtual PC, which uses the same Right-Alt UI.

    The artifacting colors are only guesses. In order to determine the correct colors I need to know the relative phase between the color subcarrier and the pixels shifted out by GTIA, which I can't determine from the specs. I tweaked the colors against Choplifter, which has the unusual combination of both artifacting and colors, but I should probably check some other games like Pitfall II and Castle Wolfenstein. I haven't been terribly happy with the color palette in general but it doesn't help that individual Ataris seem to vary significantly in color output.

    Phaeron - 07 07 09 - 16:05

    Hi Phaeron,

    Thanks for the reply, things that make the emu personal would be nice to save ie the image filter if that's possible.

    Re the palette, yup a small tweak of the screw on the Atari gives you a whole new colour system which does not help. Oh, I should have mentioned I was using the RC1 Windows 7, my apologies, I know another person on Vista has the same issue with the right alt as well which would make sense for it to carry on into Windows 7. Btw, there are loads of people with pretty nice Atari800win Plus palettes on the Atari Age forum, I found one guys version for PAL and NTSC looked very close to the million and one Atari's I sold at the time.

    Just one little last question, I run most of the games in Pal mode as I'm in the UK and I grew up with that speed of music etc so NTSC sounds too fast to the PAL ear, but I've noticed that if you stop Altirra to change a setting it seems to speed it to NSTC when it goes back in game and slowly settles back to PAL over a few seconds. Not an issue, just a bit weird :)

    Mclane - 07 07 09 - 19:56

    Here's those palettes I mentioned..

    Mclane - 08 07 09 - 00:09

    The warping of the sound is caused by a resampling controller on the POKEY output. Altirra syncs to the video display to attain frame rate lock and generates sound in sync to the emulated Atari clock, so there are sync issues if the audio clock doesn't exactly match the video clock. In order to fix this, a resampler slightly varies the POKEY output frequency in order to keep audio latency within bounds. Unfortunately, there is a problem where interruptions in frame rate cause the controller to wig out and clamp for a couple of seconds, which causes the warped tone. I tried to make some quick fixes for 1.2 but wasn't able to resolve the problem. The annoying thing about audio is that it's a real-time system, so setting breakpoints or logging to the debugger disturbs timing too much to monitor the situation -- I need a log capture mechanism to plot out what's whapping the resampler.

    Phaeron - 08 07 09 - 15:31

    Many thanks for the emulator altirra and Virtual dub.
    I wish to inform you on errors in the emulator altirra 1.2.

    Berzerk - there are no shot sounds.
    CavernsOfMars - the name on the title screen is spoilt. not work management.
    Caverns Of Mars 2 - the name on the title screen is spoilt.
    Dimension X DV - errors on the title screen.
    DROPZONE - wrong sounds after level end.
    Fantastic voyage - the ship leaves for the screen.
    KAZOO - at the second level it is invisible the hero.
    Landscape - not work.
    Nadral - the inscription before the level beginning is spoilt.
    stealth - after level end errors begin.
    vanguard - hangs by pressing up + shot.
    Warhawk - at shots the screen twitches.
    zombies - not work.
    zone x - after level end hangs.

    Please make by default Filter point.

    sorry for my english.

    breaker - 08 07 09 - 17:39

    Thanks Breaker, you certainly live up to your name :)

    Phaeron, as I said, I wondered about the syncing but please use whatever spare time you put aside for Altirra into the emulation quality, niggles can be fixed later. From the list Breaker has added there seems to be a common theme in two area's so hopefully it will be an easy fix and will cure many other unlisted games. I tried every combination of settings possible to fix said graphic issues but it's either non emulated or broken.

    Thanks again for your continued time on the project, it makes an oldie like me who was a young man when Atari came out and who later sold, supported and hacked on the old machines very happy.

    Mclane - 08 07 09 - 22:03

    Sorry, forgot to ask, when you get around to playing with what is saved as a setting could screen size and position be saved?


    Mclane - 08 07 09 - 22:06

    I from Russia and am for a long time the big admirer atari.
    Because of that that Atari800WinPlus long time does not develop,
    I will be very glad to the new emulator.
    I wish good luck Phaeron.

    sorry for my english.

    breaker - 08 07 09 - 22:13

    Breaker, do not apologise for your English, it's more than enough to understand and much better than my Russian (which is nothing).

    I'm also a long time Atari admirer and miss the update of Atari800win Plus as I was a beta tester for it. Phaeron is doing a great job so both me a UK person and you a Russian person can both admire his hard work!

    Mclane - 09 07 09 - 03:18

    Well, I will not apologise :)
    But I use programs translators, it will be sometimes very difficult to understand.

    Some more errors:

    AliBabaAndTheFortyThieves - not work management.
    amazed - not work.
    pacem in terris - not work.
    base 33 - The image is deformed.

    breaker - 09 07 09 - 03:36

    Yeesh, what a list. I've only gotten through the second set so far.

    AliBabaAndTheFortyThieves: Works, but only with a real Atari OS-B kernel ROM, because one of the disk sectors is XOR encrypted against $FF00-$FFFF.

    Amazed: ATR image floating around is bad and jams in an unexplainable BNE *-2 loop; executable version contains garbage at the end. Altirra 1.2 has a bug where if it detects this, it fails to jump to the run vector correctly -- fixed. R5 wasn't able to launch the EXE either until I trimmed it.

    Pacem in Terris: Glitch on main display is due to a late write to DMACTL to change playfield width, which I'll have to look into. The inability to load side 2 is due to a bug in my ATR routines where I was checking the boot sector for a sector count instead of just assuming 3 128-byte boot sectors when scanning the image. Fixed.

    Base 33: 320K memory mode didn't allow ANTIC bank switching -- fixed.

    Phaeron - 10 07 09 - 17:32

    I suspect for most of list one that one fix will cure all those graphic errors.

    Thanks for the fixes so far..

    Mclane - 11 07 09 - 00:34

    Please add still the second joystick on Numpad.
    and make by default Filter point.

    Very much I wait 1.3pre1 :)

    breaker - 11 07 09 - 22:15

    I don't want to make the default Point, because it doesn't look very good at lower resolutions and because I can't control the filter if DirectDraw is activated. I can definitely make that setting save, though.

    Turns out it took a lot longer than I had expected to get through breaker's first list, but:

    Berzerk - there are no shot sounds.
    KAZOO - at the second level it is invisible the hero.
    - Can't reproduce -- seems to work OK for me.

    CavernsOfMars - the name on the title screen is spoilt. not work management.
    Caverns Of Mars 2 - the name on the title screen is spoilt.
    - ANTIC mode 9 was busted. How embarrassing.

    Landscape - not work.
    zombies - not work.
    - Had to fix bugs in illegal (undocumented) instruction handling.

    Dimension X DV - errors on the title screen.
    - This game wins the award for most bugs triggered. Illegal instruction handling was also a problem here, but there are two other problems if you are trying to run this from an ATX (VAPI) image. The first is that this game relies on the undocumented value of A on exit from DSKINV, so in 1.2 it needs to be run with the SIO hook off. The second is that the sector timing is not correct and this causes the second phase of the copy protection to fail (phantom sectors in wrong order). I don't know why yet. Finally, I hadn't implemented CHACTL bit 2 (vertical reflect) for ANTIC mode 4. Whoops.

    DROPZONE - wrong sounds after level end.
    - I ran this on a real Atari 800XL, and it sounds like the audio is just clamping out. The game is doing something with the high-pass filter. I'll have to look at this further. By the way, this is an interesting Defender clone.

    Fantastic voyage - the ship leaves for the screen.
    - This was a NASTY one: turns out missiles were overdrawing and causing false missile-to-player collisions when a ANTIC-GTIA sync occurred in the middle of a missile.

    Warhawk - at shots the screen twitches.
    - Overrun in VBI routine. For some stupid reason this game waits until the very END of vertical blank to write DLISTL/DLISTH, and it turns out that I was fetching P/M graphics in v.blank which made the VBI routine take too long. I need to check this on the real Atari because the cycle counts in the Hardware Manual don't make sense. BTW, I was surprised to discover while debugging this that Atari800 is a bit sloppy and simply does all nine cycles at the start of the scan line in v.blank. It's hard to envision a scenario where this matters, but it made it a huge pain to compare cycle times.

    vanguard - hangs by pressing up + shot.
    - Couldn't reproduce (works for me), but I always thought the Atari 2600 port of Vanguard was better anyway.

    stealth - after level end errors begin.
    zone x - after level end hangs.
    - I can't finish a level in these games to check these! :)

    Great feedback, overall. I think I need to get back to VirtualDub for a while, though....

    Phaeron - 11 07 09 - 23:50

    Cheers Phaeron, don't leave us tho ;)

    Mclane - 12 07 09 - 00:58

    @Phaeron: You missed "Nadral" in the list.

    ale5000 - 12 07 09 - 11:45

    Oops, editing error. Nadral is also affected by the broken ANTIC mode 9.

    Phaeron - 12 07 09 - 12:01

    For those who are adventurous:

    Bizarre A800 trick of the day: Whoever wrote Cavern of Mars switched the second joystick port bits in PORTA to output direction just to skip one AND #$0f instruction.

    By the way, Right-Alt to unblock the mouse works for me on Windows 7 RC, so I'm still scratching my head on that one.

    Phaeron - 12 07 09 - 19:10

    Hi Phaeron,

    Thanks for those great fixes..

    Hmm..Re the Right ALT, very odd, I'm using the MS released RC1, no hacks or dodgy releases, I wondered if it was a region thing and changed all that, made no difference but then I stumbled upon one thing.

    If I press the F8 key it unlocks the mouse..most of the time...sometimes it unlocks the mouse but loses the mouse unless you ALT+TAB and refocus the Altirra window or any other window and then you get the mouse back.

    Slightly odd thing, if you regain the mouse focus by the way above and just click back in game the emulator stays as 'stopped'. If you don't go back in game and just go to load another disk its fine and works properly.

    Don't know if this helps or gives a clue re the right alt.

    Mclane - 13 07 09 - 01:17

    Edit that, if it's running in game and you press F8 then the emu screen goes white and any attempt to get into a menu causes a Altirra crash dump which I presume would be useful to you.

    Sorry for the confusion, doing 20 things at once while being mauled by my wifes new kitten.

    Small and fluffy..Yes, Sharp claws also a YES.

    Mclane - 13 07 09 - 01:24

    And to finally bore people to death re this, if like me and a few others and get 'stuck' in Altirra when the use mouse option is ticked and the Right Alt does not work then simply ALT+TAB will work WITHOUT all those nasty crashes via the other method.

    Mclane - 13 07 09 - 02:13

    As a long-ago Atari employee (and, of course, Atari owner) I am _blown away_ that you completed this work. Congrats for an awesome job!

    Weirdly, I just moderated a panel at Cisco Live with Adam Dunkels, the guy who wrote the Contiki OS for extreme power-saving sensor network applications, and it turned out that he, too, had recently finished an Atari 800 project: in his case, writing an IP stack for the box and turning it into a webserver. Would be great to get both of you on a panel together sometime soon.

    John Jainschigg, Exec. Dir., Internet and Community Lab

    John Jainschigg - 15 07 09 - 07:05

    I wish to inform you on errors in the emulator altirra 1.3 pre 3.

    ANDROID - not work.
    Anduril - not work.
    BlackLamp2 - not work.
    Chicken - Fast death.
    DARG - Too quickly works.
    flappy - Does not shoot.
    G.I.L.P. - not work.
    Galaxian - The spoilt image.

    If it is possible, add in the emulator save state, as in Atari800winPlus.

    I will test further games on your emulator and to inform on errors.

    breaker - 17 07 09 - 02:28

    - Works, but requires BASIC to be enabled.

    - Works, but requires BASIC to be disabled by OPTION on boot, and then enables it when it finishes loading. Absolutely screwy, but I checked this on a real Atari. The problem is that Altirra's BASIC option actually masks PORTB bit 1 entirely, and I need to change that.

    - I'm afraid I don't have this game available.

    - ANTIC vertical scrolling problem; fixed. Who the hell uses vertical scrolling on a blank mode line??

    - Couldn't reproduce.

    - This is a bug in the game. It reads location $00 without initializing it, and this fails in emulators because that value may be #$00, which is what breaks shooting. I'm guessing the author screwed up a patch because this bug happens to exist very close to a lone nonsensical illegal instruction.

    - Broken due to rather daring use of undocumented 6502 opcodes that I don't support (XAA, in particular). Fixed. Rumor from the C64 crowd is that this instruction is unstable, but I can't test it because this game doesn't run properly on NTSC hardware.

    - Unable to reproduce, works for me.

    Phaeron - 17 07 09 - 19:44

    Game blacklamp2 can take here

    I am very surprised, in emulator Atari800winPlus 4.0 I start game Android but a BASIC is thus disconnected.

    "DARG - Couldn't reproduce."
    You cannot start game or at you this game is not present?
    sorry, could not translate correctly.

    breaker - 17 07 09 - 22:20

    Darg - Must turn off accelerated floating point otherwise too fast.

    Moral, run the games as near as to the real hardware when testing

    Black Lamp 2? I'm presuming its Black Lamp (v2)ie a different crack / version. Needs to be set to XL and PAL otherwise it dies.

    Galaxian - If in XL mode it has flickering top and screen but in 800 O-SB its fine..Emulation fine..

    Mclane - 17 07 09 - 22:24

    Breaker, use the settings I've posted for each, just tried the file you posted and it is indeed Black Lamp (v2) just differently named.

    Can't reproduce means he ran the program and it worked fine, he could not make it do the error you posted.

    Again see my post as to how to make it the right speed.

    Mclane - 17 07 09 - 22:38

    Breaker, thanks for your testing and PLEASE keep it up but remember that some programs need BASIC, some won't work on different television systems probably due to sloppy programming in use off timing. It's worth noting that Altirra offers additions to the normal hardware like SIO patching for speed loading, floating point and various versions of an OS which will affect a certain number of titles that still have some checks for being hacked so run it as near as real hardware.

    I can't answer for Phaeron but I'd love you to carry on testing stuff as you have brought out some great issues that once fixed makes Altirra better and better..Cheers from a windy London.

    Mclane - 17 07 09 - 22:48

    I will check further games and to inform you on errors.
    I check all in alphabetic order.

    breaker - 18 07 09 - 02:47

    more errors

    Grab An Apple - Too quickly works.
    Grow Worm - Too quickly works.
    HalleyProject - not work.
    JurassicPark - not work.
    kaboom - not work management.
    kasiar - The timer is spoilt.
    Keychase - Too quickly works.
    Knock! - not work.
    lord of the orb - If to press fire + to the left + to the right the hero will get stuck.

    breaker - 19 07 09 - 23:08

    Grab An Apple - Too quickly works.....Turn off accelerated floating point...

    Grow Worm - Too quickly works......Turn off accelerated floating point...

    HalleyProject - not work...Works for me try same fix and try PAL and different OS's

    JurassicPark - not work...This does die,,Will try more checks

    kaboom - not work management....OS-B only

    kasiar - The timer is spoilt....Can't read German but betting its the Floating point being on again.

    Keychase - Too quickly works....Floating point on again., must be off

    Knock! - not work...Dies while unpacking, suspect weird opcode?

    Can't test Lord of the orb at the mo as my dodgy driver for my modem locks the modem port if my USB joystick is in..Useless Zoom programming..

    If the game is too fast in any way then make sure the floating point is OFF, normally that's the only thing needed..

    Mclane - 20 07 09 - 01:22

    MAZEWAR - not work.
    Meteor '84 - Game should work from the second joystick.
    NAUTILUS - Game should work from the second joystick.
    PolePositionRaceDesigner - not work.
    pong - not work management.
    pong (v4) - not work management.
    PreliminaryMonty - Wrong sound at a capture of things.
    Pungoland Construction Set - not work.
    QB - not work.

    breaker - 21 07 09 - 20:15

    MAZEWAR - not work....Confirmed..

    Meteor '84 - Game should work from the second joystick...Yes, needs emulation of 2nd joystick

    NAUTILUS - Game should work from the second joystick......Ditto..

    PolePositionRaceDesigner - not work....Version 3.01 works for me

    pong - not work management...Works for me but think it needs joystick 2 (or 1)

    pong (v4) - not work management....Works for me but again seems to want an alternative joystick port.

    PreliminaryMonty - Wrong sound at a capture of things...Confirmed, correct sound but with an added noise

    Pungoland Construction Set - not work....Confirmed..

    QB - not work....Works for me, suggest you might have missed a mode ie PAL not Pal.

    Mclane - 21 07 09 - 22:26

    To clear up QB, must be OS-B

    Mclane - 21 07 09 - 22:28


    There are 5 versions of Maze War, Maze war (v1) and the .atr version do not work on any machine ie Atari800win Plus and I suspect are bad dumps.

    The same Applies to Pungoland set, it's actually marked as a bad dump so it does not work on a real machine or emulator.

    Mclane - 21 07 09 - 22:43

    Sorry about the multiple posts Phaeron, just trying to weed out the things that are fine and just leave you the 100% faults or needed features.


    Mclane - 21 07 09 - 22:47

    Thanks, I wait version 1.3 pre5.
    I hope Phaeron has not forgotten about this page?

    I wish to inform on one error.
    There are 9 variants of game Alley cat, but two variants are loaded only:
    Alley Cat (v2).atr
    Alley Cat (v3).xex
    The others are not loaded or on the first screen of game give out a wrong picture.
    Used any options for the emulator altirra, does not help.
    On emulator Atari800WinPlus 4.0 - 9 variants are loaded all!

    breaker - 22 07 09 - 00:00


    I'm still on pre1??

    But re Alley cat it's as Breaker says, as soon as you start a game the backgrounds and sprites are corrupted on certain version while Atari800win is spot on.

    Mclane - 22 07 09 - 01:28


    I'm sure Phaeron see's the page but you have to remember he also produces the amazing virtualdub software and that's his main development work, Altirra is just a part time experiment (well that's how it started).

    He's also entitled to some free time away from the keyboard ;)

    Mclane - 22 07 09 - 01:32

    I hope that the author will not throw the project, I think it the excellent emulator for which there will be a future.

    Mclane, there were other versions of the emulator.

    breaker - 22 07 09 - 03:02

    Thanks Breaker, I did wonder where you got the link from so I just copied the beta one location and changed it to 4 and bingo, there it was..

    Wonder what the changes were?

    Mclane - 22 07 09 - 04:31

    By all means, please continue logging results here. Doing so means I have a place to go to when I resume. But yes, I've been taking a little break from Altirra, since I was spending too many consecutive nights on it. I'll get back to it at some point.

    1.3 pre-4 was a private release I sent someone to address a reset problem he was seeing while trying to work on his A8 project. (Atari changed the way SYSTEM RESET works between the 800 and the 800XL.) It does contain some fixes for bugs since the 1.3 pre-3 release I posted here, such as the illegal instruction problems that were keeping G.I.L.P. from running. As anyone who's run test releases of VirtualDub from my forum can attest, the pattern I use for test release filenames is pretty easy to figure out. All changes that I make, by the way, are always documented under Help / Changelog. It isn't always clear what programs are affected, but that's where you'll find the full list of what's been fixed or added.

    Alley Cat is an interesting case. That's a game I used to play a lot when I was growing up, and I seem to recall that I had to use the Translator disk to get it to run on my 1200XL or 800XL. I don't know if this behavior is specific to a certain build or not. The version I have now seems to work fine on an XL, which is weird.

    Phaeron - 22 07 09 - 15:09

    Thanks for the update Phaeron, as regards alley cat, there are several releases of it and all boot on Atari800win so we can they are not bad hacks. I did notice that the debugger showed a 'bad' in the opcodes / dissembley window so I presume it's either a bad opcode or an unregognised one hence the fail?

    Mclane - 23 07 09 - 01:15

    Thanks Phaeron, please do not throw the project, at you the excellent emulator turns out, it will be good replacement old Atari800WinPlus.
    Very much it would be desirable to see in the addition emulator:

    1) the second joystick.

    2) save state of game in the form of files a8s (not quick save).

    3) a qualitative sound.

    I will continue to test further the emulator and to inform you on errors.

    breaker - 23 07 09 - 01:52

    Alright, I fixed a few more bugs:

    Specific issues:

    - This game's loader has a really bad bug: it loads on top of the active display list and then enables DLIs before waiting for the new display list to take effect. It just happens that this causes the display list to "terminate" with a wait for vertical blank instruction that has the interrupt bit set, which causes an interrupt on each scan line. The catch is that ANTIC hits that instruction before DLIs are enabled, and in some settings the interrupt spam causes a crash. I need to check behavior of this on a real Atari since I think I need to adjust the interrupt handling here. On the bright side, I found a bad bug with the "accurate disk timing" option, which was also delaying status requests. It now has no timing effects when SIO acceleration is enabled.

    Jurassic Park
    - $C2 illegal opcode was wrong; fixed.

    Alley cat (some versions)
    - $BF illegal opcode was not correct; fixed.

    Lord of the Orbs
    - Has a bug where it malfunctions if left/right or top/bottom joystick switches are set. The front end no longer allows this; fixed.

    - Could not reproduce, works for me.

    Preliminary Monty
    - This game "mutes" audio channels by letting them play at frequency 1 (15KHz). This is aliasing down due lower frequencies due to the crude resampler that I'm using, which I need to improve. Not yet fixed.

    Phaeron - 23 07 09 - 19:58

    Phaeron, You missed "kasiar" in the list. :)
    In game kasiar, in the bottom part of the screen there are hours, in the emulator they look incorrectly.

    I think that in game "vanguard" an error such as well as in game "Lord of the orb".
    If to press fire + up or fire + down - game hangs.

    Alley Cat.xfd and Alley Cat (v5).xex not work.

    game A.R.O.P.xex - not work.

    I wish to inform that now game "Stelath" works normally.
    Game "Zone X" - any level it is possible to work, but there is an error with teleports.
    If you will make normal save state (not quick save) I will make to you preservation before an error.

    Also I have found completely the working version of game "maze war" can take here

    breaker - 24 07 09 - 15:42

    I did a bunch of work on the illegal instruction support and added joystick 2 mode:

    kasiar: Same problem as Pacem in Terris -- late write to DMACTL to change playfield width. I've implemented support for that and both should now work properly. Interesting game, but it's a horribly complex maze. Reminds me of Zak McKracken.

    Alley Cat: Sorry, but I can't tell what versions those are. I've gotten the ones that I have to work.

    AROP: Cannot reproduce, works for me.

    Vanguard: Cannot reproduce, works for me.

    It's unlikely that I'll be able to implement a8s support right now since I haven't found any documentation on the format, and it's probable that the file doesn't contain enough information to reconstruct internal emulator state (this is an entirely different emulation core than atari800). I could implement save to file, but the problem there is trying to maintain support for a stable format. Right now the save state works by just serializing internal structures, which means that just about any change to the emulation algorithms would invalidate the save format.

    Phaeron - 25 07 09 - 12:30

    Thanks, Phaeron.
    Games "vanguard" and "kasiar" completely works.

    But I do not understand what for was to put the second joystick on arrows?
    Why have not put the second joystick on Num pad (Numeric pad)?

    Please, put Joystick #1 on arrows, and Joystick #2 on Num pad.
    Only at such apportion it will be possible to play together.

    I will test further the emulator and to inform you on errors.

    breaker - 25 07 09 - 16:45

    I added the second joystick as interim support to unblock games that require joystick port 2, not as a real multiplayer solution. I'm on a laptop, so the num pad is rather inconvenient for me....

    Note that although it's undocumented, Altirra will pick up a game pad as joystick 1.

    Phaeron - 25 07 09 - 17:14

    Means other variants of management for Joystick #1 and Joystick #2 will be added later?
    I have checked up games using Joystick #2, games work perfectly.

    breaker - 25 07 09 - 19:27

    Phaeron, regarding Alley Cay an AROP, there are multiple dumps of these, most work as is but there are two that fail on Altirra. If you want any of these to test then mail me at (remove the plop) and I'll gladly send them.

    Mclane - 26 07 09 - 00:54

    Ratapede - not work management.
    Realx - not work management.
    Speedway Blast - At shooting on opponents the emulator hangs.
    Spy Vs Spy (v1).atr - not work.
    Spy Vs Spy (v4).atr - not work.

    I have found an interesting disk with several games.
    On emulator Atari800WinPlus 4.0 disk works normally.
    In the emulator altirra the disk menu is not displayed.
    can take here

    breaker - 27 07 09 - 04:37

    Alley Cat (v5)
    - Problem with $BF illegal opcode. Fixed.

    - Issue with EXE loader. Fixed.

    Star Maze
    - The loader menu for this image is VERY buggy. The main problem is that it does not wait for the VBI routine to set the new display list before replacing VVBLKI. The result is that the display is wrong if SIO acceleration is enabled because the load happens so fast that a VBLANK doesn't occur before the load has finished. There are other problems with this loader, such as bogus disk write commands to random sectors and crashing if you press an invalid key. I don't think it's worth trying to fix this.

    Ratapede, Realx:
    - These appear to work, but require paddle controllers, which I don't support right now.

    Speedway Blast:
    - Problem with $AB illegal opcode. Fixed.

    Spy vs. Spy:
    - This game wins the Stupid Atari Trick of the Day award for using the joystick port output register (PORTA) to hold an XOR encryption key. Fixed.

    Phaeron - 27 07 09 - 17:40

    When you find an illegal opcode do you just nop them so processing carries on?

    Mclane - 27 07 09 - 23:09

    Phaeron, is it just me or is there a very very slight lag in joystick response?

    I was playing Buried Bucks which is a friends fave old game and we both seem to think it's a tiny bit less responsive than Atari800win, different PC, OS's and joysticks. DX is up to date on both.

    I don't know how you would gauge it on a real Atari and it could be that it's unrealistically faster on Atari800win. Btw, being played in PAL an both machines, ie one person ism't in PAL and the other in NSTC


    Mclane - 28 07 09 - 01:54

    Some more errors:

    Star Sentry - After loss of a life the emulator hangs.

    storm - not work.
    From 6 variants of this game one loaded only.

    Tarzan of the Apes - Inscriptions in the menu are incorrectly displayed.
    Tarzan Of The Apes (v1).xex - not work.

    TURMOIL - Indications of score are shifted downwards on a line.

    vanguard - In last zone with the boss, the emulator hangs.

    ZEBULAND - not work.

    Thanks for addition of a qualitative sound.
    But in game Berzerk - there are no shot sounds.

    I have downloaded from a site all games and I will check further the emulator.
    If I find still errors to you I will inform.

    breaker - 30 07 09 - 00:35

    Phaeron, you can add in the emulator:

    Filter mode - Scanline.
    Save screenshot. ?

    breaker - 31 07 09 - 18:01

    Star Sentry - After loss of a life the emulator hangs......OSB fixes that, v2 of it hangs on load with a bad instruction

    Storm....Tried everything, it does not lock the emu but it just seems to be locked in some cycle internally. Also does not work on Atari800win plus 4.0

    Tarzan...Confirmed titles corrupted, suspect being displayed in wrong mode.

    Turmoil........Odd one this, in Altirra the score looks like it's lost a scan line at the bottom, but in Atari800win's weird, it looks like it's been shifted UP and lost a scan line at the top..

    Vanguard...Pass...Kept dying..Will cheat it and retry :)

    ZEBULAND.......Port one fire button causes reboot...

    Mclane - 31 07 09 - 22:44

    Also, Berzerk, it depends which version you try, there's v3 version which indeed does not have sound for shots but does work correctly in Win Plus. Tried numerous configs and it still remained soundless for the shots, all other sounds seemed ok.

    Mclane - 31 07 09 - 22:56

    I'm still running through the list, but:

    Star Sentry (v1)
    - Incompatible with 800XL kernel due to overwriting cartridge checksum.

    Star Sentry (v2)
    - Seems to work for me.

    - Confirmed, but not fixed yet. The corruption is due to a DLI that has extremely tight timing tolerances for reading VCOUNT, and for some reason under Altirra it is hitting the DLI 1-2 cycles too early.

    - Change the disk mode to Virtual Read/Write. This game writes to disk sector 8 to record that it should skip the opening screen, and by default Altirra opens disks in read-only mode so that it doesn't modify the original disk image files. (I _hate_ that behavior in A800Win!)

    - Confirmed, not fixed yet. This game was ported from the Atari 2600 and has some really evil mid scan line changes, so I need to check this on a real Atari and trace the timing. BTW, this game is one of my 2600 favorites, even though it's a fairly simple game.

    Phaeron - 02 08 09 - 14:32

    Phaeron, You missed "Storm" in the list.

    In game Oils Well, a wrong sound during collecting of points.
    And a flickering strip from above at the fifth level.

    Oils well, River Raid and Boulder dash it perhaps my favourite games. :)

    And still I wish to tell about cartridges.
    I managed to collect 80 images of cartridges, from them 72 files (rom) and 8 (bin, car).
    Any of images to me did not manage to be started on Altirra, on emulator Atari800WinPlus 4.0 all 80 images work.
    Emulator Altirra does not understand files (rom).

    I have laid out images of cartridges here. [ed: link removed]

    breaker - 02 08 09 - 17:08

    If I haven't mentioned to an item on the list, maybe it's because I haven't gotten to the damn item on the list.

    Phaeron - 02 08 09 - 17:20

    New build:

    This build fixes problems with Turmoil (DMACTL changes weren't causing an ANTIC-GTIA sync) and with Tarzan (VCOUNT was one clock too late... sheesh).

    Also, this version adds commands for disabling collisions between players and missiles and with the playfield, for cheating purposes.

    Update on Zone X: The teleport crash appears to be a bug in that particular version of the game. There is code that is reading an uninitialized page zero variable ($C2) and executing an errant PLA instruction as a result. I got it to crash on Atari800Win as well. I'm guessing that this is due to a patch of some sort since I can't imagine that the original game shipped with broken teleporters (although I might be wrong, given how damn hard this game is).

    Altirra's cartridge support is VERY minimal at the moment. Right now, it only supports 8K, 16K, 32K XEGS, and AtariMax Flash 1M/8M carts. I haven't bothered to go back yet and add support for the 158237 kinds of cartridge mappers that A800Win supports. Fortunately, those are very well documented and not too hard to do.

    Phaeron - 02 08 09 - 19:59

    Phaeron, big to you thanks that you do not throw the project and forgive me for my impatience :)

    I have checked up Cheat mode in several games (Jet set willy, PreliminaryMonty, Berzerk) all perfectly works.
    Though in game Boulder dash for some reason Cheat does not operate.

    Concerning games Zone X, I have been very surprised when have checked up today a place with teleports on emulator Atari800WinPlus and also have failed.
    I played one month ago Zone X and crash not was, I not understand than it is caused.
    At me the image of the cassette "Zone X" has remained, I have checked up it on emulator Altirra.
    Errors with teleports are not present.

    I spread here an image of the cassette and the disk made of it.
    Please, if can, check up an image of a disk.
    I can be wrong converted the cassette ?

    Image of the cassette precisely working, I have checked up.

    breaker - 02 08 09 - 21:47

    Has forgotten to tell, when will load an image of the cartridge "Zone X", disconnect Sio patch.

    breaker - 02 08 09 - 21:52

    Thanks for your work as usual Phaeron, forgive Breakers enthusiasm, he just likes what he's seeing from your work. Please don't stress yourself out re Altirra, I'm one of the older people who uses emulators (48 to be exact) but I totally respect your time and work and hope you can fit a little time as and when you can for Altirra BUT Love, life and main work ALWAYS come first especially If you are a parent as in my case....Thank you...

    Here are a few things I'd love to see in the emu as cosmetic things if possible.

    One of my idea's that came to be for Atari800win Plus was a sector counter, not just a drive number, handy to see if a drive is stuck on a virtual bad sector from a corrupt image.

    Vsync if at all possible..

    And lastly, a way to turn the cassette loading symbol off after using it, it stays there until you shut down the emu no matter what you are doing :)

    Oh, info for anyone using Kaspersky Internet Security on Windows 7 (may be the same on Vista and XP), make sure you promote Altirra to the trusted zone in Kaspersky, by default its placed in the restricted zone which inhibits some of Altirra's workings hence a white screen if you turn on the debugger and a few other things.

    Mclane - 04 08 09 - 22:22

    Mclane, I too wished to tell about sector counter, but have decided not to distract yet the author, at first it is necessary to make full compatibility of the emulator with a software.
    Also I wish to tell that the emulator does not hold correct speed of emulation.
    At me in mode PAL, in a window, the emulator gives out 50.3xx FPS.
    In Full Screen stands out from 51 to 53 FPS.

    Most of all I wait for addition in the emulator save states (not quick save).
    And num pad keys for joystick #1 and #2.

    I continue to test the emulator and I inform again on errors:

    storm - not work.
    Aerobics - not loaded..
    Alex - not work.

    My computer:
    Intel Core 2 DUO E8400 3.6 Ghz.
    RAM 4.0 GB
    Nvidia GeForce GTX 260
    Windows Server 2008 Datacenter.

    breaker - 05 08 09 - 13:10

    - Fixed: The self-test ROM isn't supposed to appear if the kernel ROM is disabled. Funny how NO ONE mentions this when discussing PORTB banking, not even Atari....

    - Fixed: Illegal instruction handling fixed.

    - Fixed: Illegal instruction handling fixed.

    The PAL frame rate was indeed off slightly -- it now targets the correct 49.86Hz.

    I haven't bothered to put in a sector counter yet because (a) the way I have to display status on-screen right now in code really sucks, and (b) the debugger shows disk sector activity if you have it enabled. That's usually how I debug disk related problems.

    The emulator does do VSync, but it can be problematic in windowed mode -- Altirra does it slightly differently than the normal way because the standard Direct3D way causes input lag problems. It should work more reliably in full-screen mode, where I use regular flipping.

    The cassette support is pretty raw in general right now -- the reason the indicator stays up is that I don't even have a way to eject the tape! I need to redo a bunch of the code, because it doesn't even support non-standard baud rates.

    There's nothing I can do about Kaspersky breaking my app. I don't even have any networking code in Altirra.

    Phaeron - 09 08 09 - 10:56

    Phaeron, many thanks to you for excellent work.
    The sound became even better, FPS keeps nearby 50 and has earned the majority of cartridges. :)

    Some games do not work:
    Tarzan Of The Apes (v1).xex

    I also hope that you can solve a problem with games AliBabaAndTheFortyThieves and Dimension X DV.

    Strange error with game Berzerk.
    In variants of game Berzerk (v1).atr, Berzerk (v1).xex, Berzerk (v2).xex - the sound from shots is.
    In variants Berzerk (v2).atr and Berzerk (v3).atr - sounds from shots are not present.
    On emulator Atari800WinPlus 4.0 in all variants of game there is a sound from shots.

    Errors with cartridges:

    Air Wolf_Monkey Magic_Moon Patrol_Sea Dragon_Spiky Harold_Milk Race_Rally Speedway.rom
    Mean 18 (v1).rom
    Mean 18 (v2).rom
    MIDI Maze.rom
    One Moon And Two Suns (demo,v1).rom
    One Moon And Two Suns (demo,v2).rom

    These 8 cartridges are not started on the emulator altirra.

    Very much I hope that in following release of the emulator keys (Num Pad) for joystick will be added.

    breaker - 09 08 09 - 20:50

    Phaeron, thanks as usual for a new update.

    Regarding the Kaspersky, that wasn't a thing I was suggesting you fix :)

    Was just a heads up for anyone having problems with the emulator under it, thanks for the explanations for the other stuff...

    Mclane - 10 08 09 - 00:26

    Tarzan of the Apes (v1).xex:
    - Fixed: Added workaround for bad executable.

    - Fixed: Disk boot flag is now set prior to running executable.

    - Fixed: Asynchronous serial receive mode no longer holds down timers 3 and 4 permanently.

    Most/all of the cartridge problems are due to cartridge images that don't have a header and thus don't indicate their mapping mode. Atari800WinPlus works around this by asking the user; I haven't gotten around to doing something similar. Part of me wonders if it might be possible to guess....

    Phaeron - 17 08 09 - 10:03

    Thanks for another update..

    Re the carts, you could always do a generic auto selection and if it fails then a 'load as' option.

    Mclane - 17 08 09 - 20:15

    Thanks for update. :)

    more errors:

    Arkanoid (v4).xex - not work.
    Assault Force 3-D.atr - Game hangs.
    Asteraxis 2K - not work management.
    Atari Blackjack Casino - I could not understand as correctly this game should work.

    breaker - 18 08 09 - 02:40

    Arkanoid (v4).xex - not work....Needs OS-B, works fine..

    Assault Force 3-D.atr - Game hangs....Looks like a bad dump, fails on Atari800win as well. Other dumps of the game work fine..

    Asteraxis 2K - not work management....Paddles not emulated so won't work properly but it does run and if you use the arrow keys it will actually play..

    Atari Blackjack Casino.......Works but suffers what looks like a sprite with a bad data pointer.

    Mclane - 18 08 09 - 03:40

    Atari Blackjack Casino:
    Working correctly. I ran this on a real Atari and it also displays garbage along the right side. I'm guessing this is a bad dump, although honestly, I've never seen so many DLIs for such a boring screen....

    Assault Force 3-D:
    This one is actually interesting. It turns out that this game requires a math acceleration cartridge to work ( This cartridge exposes a hardware multiply/divide at $D5xx. As a result, you won't generally get this to run either on a regular Atari or on an emulator, with the exception that supposedly there is a patched Atari800 (NOT Atari800WinPlus) version that can run it. The functionality is sufficiently simple that I might just add it to Altirra just for kicks. The funny part is that the multiply part at least was unnecessary, because you can do an 8x8 multiply software about as quickly as it takes to do it through this chip (~26 clocks with table based method).

    Phaeron - 18 08 09 - 08:30

    Odd, I have a different dump of Force 3D and it works perfectly on Altirra..

    Mclane - 19 08 09 - 02:17

    According to that thread, someone managed to patch the game to not require the cart (which tells you how useful it actually is).

    Phaeron - 19 08 09 - 18:25

    Aha....Sorry, didn't read the thread, will now...

    Mclane - 19 08 09 - 23:33

    Hi, im the creator of the Atari800 gamebase and im really impressed by your emulator. I’m having trouble getting it to load images other than disks, are there any command line arguments to specify what type of image to run on the emulator, ie –cart to load a cartridge or –tape to load a cas file.

    hardman - 20 08 09 - 00:54

    Great work. I'm also impressed.

    1. File > Cassette > Load > [.cas file]
    2. hold shift f2 + do a warm/cold reset & boot without BASIC
    3. press RETURN ;)

    Loading WAVs don't work for me ("A fatal error has occured...") - I can't wait for proper, real-time cassette emulation with beep & fart noises! :)

    mic - 20 08 09 - 07:15

    Atomix Plus, The.xex - not work.

    breaker - 20 08 09 - 18:18

    @mic, Hardman is looking for the command line arguments so he can create a script for Gamebase Atari to use, without command lines he won't be able to include this lovely emu in the Gamebase.

    @Hardman : Hello there, It's Paul from the GB forum, the bloke from London that gee's you up re new versions,. Well where a new version :)

    Only joking, the last time I asked it was sometime in the year...

    Btw, you should be getting the beeping and farting I/O noise in the last pre release Pre 10 although I think the SIO speed hack isn't working in this release (wasn't expecting to hear loading noises with it enabled and seemed same speed as normal?)

    I can only imagine there will be no WAV emulation as there's inbuilt CAS emulation which is the same (I think)

    Mclane - 20 08 09 - 22:02

    I had introduced a couple of serious bugs into the cassette code: one was a bug in the audio path that was corrupting the event list and causing a crash, and the other broke WAV support. Oh, and I hacked in paddle support because I felt like getting Kaboom! working for some reason.

    Altirra is actually primarily geared to take raw WAV files. When you feed it a CAS file, it actually converts the CAS image into a decoded tape and uses that instead. Altirra's WAV input path is modeled after the way that the 410 recorder actually works, which is a pair of bandpass filters through a comparator that pipes onto the SIO bus. It's designed to be more robust than decoding by zero-crossing (WAV2CAS method), and it works on the one fairly old and distorted tape that I have. I'm interested in hearing if anyone gets it to work on a tape with non-standard baud rates, though; I had to rewrite it because the old method used thresholds that were hardcoded to 600 baud, and that's no good since the baud rate isn't known until program load occurs.

    Note, however, that the reason I added cassette support in the first place wasn't actually to read program cassettes. The reason I originally added it was that I was prototyping a program that was using the cassette deck for interactivity with audio playback. That's why the cassette logic supports non-standard data layouts and why it supports audio. You actually aren't supposed to hear the data track when loading a tape on a 410, but you hear it in Altirra when loading a CAS file because when there is only a data track, it is replicated to both channels. If you load a stereo WAV file, the left channel is interpreted as data and the right channel plays as audio. I don't actually have an image of a real Atari tape that has an audio track, though, and it's been a while since I used this, so it's likely that I either got the channels backwards and/or have messed up the playback rate at some point.

    One common cassette program loader (Enigma Loader) hacks SIO to speed up cassette loading. Cassette boots are relatively quick because the kernel boot code calls into SIO and block copies each sector out, but any subsequent CIO-based loads are slow as molasses because CIO does byte-at-a-time reads, and C: doesn't do the burst I/O hack that DOS's GET BYTE handler does. Enigma Loader bypasses this by supplying a custom cassette handler. It also copies the Atari kernel ROM into RAM, which is the bad part -- for safety, Altirra only allows acceleration hooks to activate in ROM. That leads to the weird situation where tapes using that loader will turbo load in Altirra only when 400/800 hardware is enabled, because that mode blocks the ROM kernel copy that deactivates the SIO hooks.

    A side feature that I want to stick in at some point is the ability to rewrite clean tapes from the in-RAM decoded image. The main thing blocking this at the moment is that the decoder is infinitely sensitive, which means right now it would blast out a whole lot of data noise during the leader. It needs a noise detector and silencer. Image repair is one of the weird things that Altirra is usable for -- I've used the Disk Images dialog to repair some ATR images that R5 Loader refused to mount.

    Phaeron - 21 08 09 - 18:45

    WOW ! SUPER ! Big thanks :)

    I have checked up some games using device "Paddle".
    Games perfectly work.

    pong (v1)
    pong (v4)

    I could not understand what device game "Ratapede" should use.

    It seems to me that sensitivity of a mouse in the emulator more slowly than should be.
    The device "paddle" in the emulator is not disconnected, that it to disconnect the emulator it is necessary to restart.

    I very much hope that in the emulator the device "light gun" will be added.
    To check up the device "light gun" it is possible on game "Bug hunt".

    Still I wish to ask that the option "Attach special cartidge--> SuperCharger 3D" does ?

    breaker - 21 08 09 - 21:04

    Booting form WAV files now works in pre11. I've created a WAV file from River Raid CAS file using CAS2WAV.EXE. The game loads successfully.
    CAS2WAV creates a 44kHZ, 8-bit mono PCM WAV file (there are several command line switches allowing to modify the tone waveform, custom baud rate - from 425 to 875 - and mark/space tone frequencies). I was disappointed not to hear the waveform noise in Altirra (only those GTIA(?) beeps) so I converted that WAV file to stereo in Audacity.
    The game boots fine but the waveform (right channel) playback is far too fast and GTIA(?) beeps are not synchronised with waveform data played from the right channel. I tried both PAL and NTSC using different WAV files.
    I'm not sure if it's a bug in pre11, or if it's not even implemented yet (or am I missing something), but I hope that eventually we'll get perfect waveform noise playback / emulation even from monoaural WAV files or CAS files - it would really be a breakthrough in Atari emulation ;)

    mic - 21 08 09 - 23:06

    >Still I wish to ask that the option "Attach special cartidge--> SuperCharger 3D" does ?

    If you enable it and then run assault force 3d the game now boots, it emulates the maths chip used for that game. There are hacked versions of the game (look for Assault force without the 3D).

    @Phaeron, thanks again for the update, I was lost about 5 secs into your very detailed explanation of cassette i/o but I appreciate the extreme workings of yourself.

    Silly question, have you thought about Happy Drive emulation, I know it's not really stunningly useful and certainly not a feature needed until emulation quality and compatibility is to your liking but it would be a novel eye candy feature.

    Mclane - 21 08 09 - 23:16

    I fixed the busted audio playback constant. Note, however, that the audio track is internally downsampled to 4KHz, so it won't sound very high quality.

    I never had a Happy Drive, so I don't know what the point would be besides to speed up disk loads, of which there are already methods available. I probably know enough to emulate the 810 drive itself, but it's a pain since it bit-bangs data across the SIO bus with the 6507 itself. Emulating the disk directly isn't nearly as attractive as it is on, say, the C64 + 1541, since the stock Atari disk interface didn't allow you to upload code to the drive.

    As for emulation quality, well... there's ALWAYS room to improve emulation quality. :)

    Phaeron - 22 08 09 - 10:39

    Thanks Phaeron AGAIN :)

    The Happy drive idea was just a last eye candy add on and certainly isn't anywhere needed as you already have fast booting. It was just an oddball idea as I don't think any emulator supports a Happy Drive as made by Scott Addams brother, always make me laugh that one brother made games and the other brother made hardware to copy games.

    Oh, just a note, Cassette fast I/O seems to be broken, I don't know if this is planned because you are working on that side or it's just happened. I love the loading i/o noises that you have emulated but I don't like the slow speed :) (I know, there's always someone moaning :)

    Mclane - 22 08 09 - 22:11

    Arkanoid (v4).xex - not work.
    Asteraxis 2K - not work management.
    Atomix Plus, The.xex - not work.
    Bubble Bobble (demo,p2,v2) - not work.
    Bubble Bobble (demo,p3) - not work.

    Errors with cartridges:

    Air Wolf_Monkey Magic_Moon Patrol_Sea Dragon_Spiky Harold_Milk Race_Rally Speedway
    Mean 18 (v1).rom
    Mean 18 (v2).rom
    MIDI Maze.rom
    One Moon And Two Suns (demo,v1).rom
    One Moon And Two Suns (demo,v2).rom
    Leo's 'Lectric Paintbrush.rom - not work management.
    Letter Tutor.rom - not work management.
    Bounty Bob Strikes Back!.rom - Unsupported cartridge size.
    Karateka.rom - not work.

    breaker - 24 08 09 - 21:50

    Arkanoid (v4).xex - not work......Note, this is the xex version and not the atr which is a different version again. Seems to be hitting a 'bad code' not long after initializing at $0500

    Asteraxis 2K - not work management...Does work but not stunningly well at my end with the simulated paddle, mouse seems to go from say 10'oclock to 2'oclock but no other directions.

    Atomix Plus, The.xex - not work. Hits illegal after init..

    Bubble Bobble (demo,p2,v2) - not work....Another illegal hit

    Bubble Bobble (demo,p3) - not work....Ditto...Same coding too

    Roms not looked at because known issues with some roms due to size and or header

    Mclane - 25 08 09 - 01:55

    Minor updates:


    Arkanoid (v4).xex
    - Fixed: Undocumented DCP opcode was not implemented correctly. This might fix some other programs.

    Asteraxis 2K:
    - Two issues. First, the game says press button on paddle #1, but it is actually waiting for the button on the second paddle. Second, it needs two paddles, and I only emulate one. It uses the two paddles as essentially a 2D controller, which is how it picks up the mouse in an emulator.

    Atomix Plus:
    - Fixed: This game has a bug in its loader that happens to work on a real Atari. While copying into memory underneath the kernel ROM, it enables and disables the kernel ROM on a byte basis and the bug is that it enables interrupts BEFORE enabling the kernel ROM. Altirra now suppresses any NMIs that are enabled less than three cycles prior to the trigger time; I need to verify the exact timing for this on real hardware.

    Bubble Bobble (demo,p2,v2) (demo, p3):
    - Not a bug: These two programs have a bug where they copy the kernel ROM into RAM and then accidentally stomp part of the SIO routine during load. It works on Atari800Win because that emulator allows SIO hooks in RAM, whereas Altirra doesn't allow that. If you disable the SIO patch, the demo crashes.

    I noticed the UI glitch with the paddle menu option that breaker mentioned -- I'll fix it later. I suppose I should actually release 1.3 at some point....

    Phaeron - 25 08 09 - 20:41

    Any chance of .bas file support as well as command line arguments support

    hardmanm - 26 08 09 - 02:32

    Unlikely on the .BAS file support -- not seeing a compelling reason. If you want, you can load them through H:.

    As for command-line arguments, some do exist (/? for help), so you'd have to ask for specific ones.

    Phaeron - 26 08 09 - 12:01

    I too as well as hardmanm, wish to see in the emulator support of such files as:

    I hope that loading of such files will be added later.

    I wish to inform also on two errors connected with the emulator interface.

    1) In menu Attach special cartridge it is possible to choose SuperCharger 3D.
    But thus the option is not marked.
    Because of what becomes not clear this function is used or not.

    2) If to press a mouse the top part of menu Display, the window will be allocated.
    At following start of the emulator it will not be visible images.
    Change of options does not help.
    Unique way to return the emulator in a working condition - clear all settingss.
    In your emulator there is no option clear all settings!
    I have made the small program which clears all options of the emulator.
    Please add an option "clear all settings" in the following release of the emulator.

    It is possible to take the utility here:

    breaker - 26 08 09 - 18:26

    I checked the command line options like you said, the trouble is Altirra will only load disk images through command line, which is ok for disks, but not for tapes, carts, or XEX files. To use in my gamebase i need to be able to tell the emulator to load other file formats as well as disk images using command line arguments like the ones used in atari800win. e.g altirra -cart filename.bin or altirra -tape filename.cas.

    I have been testing it in my new version of gamebase and it looks great with disk games. I would like to include it with my next release as the default emulator. I do need .bas support as well due to alot of games in my gamebase are .bas files and only work in an really old atari emulator, i would really like to use then through Altirra.

    hardmanm - 26 08 09 - 21:29

    Hi Phaeron, can I just confirm re those command lines it would be a great way to showcase the emu as many people follow both Gamebases and Hardnman's own one. It would also bring the emulator into line with all others re the ability to load via a universal loader program.

    I suspect bas and exe being the most pain ones as they have to be injected as opposed to just altering the loading code for XFD, CAS and XEX headers. Rom would also be nice for carts but as you are already working on the bad header odd size carts already I think I'd be pushing my luck :)

    Please give it some thought, Cheers Paul.

    PS. @Hardnman, there's always changing he XEX's to ATR but that's a huge job...

    Mclane - 28 08 09 - 00:45

    I've modified the File > Open command and the command-line loader so that they can load disk, cassette, cartridge, and executable images.

    The emulator now also accelerates the cassette open vector call to skip the press-play beep and the nine-second motor start delay, so it should be much faster to load cassette tapes, at least the parts that use the kernel loader.

    I'm not sure about what to do about .BAS files yet. Cassette and tape are easy to accelerate because they have well-defined hardware or kernel interception points. The same isn't true of BASIC.

    Phaeron - 30 08 09 - 09:29

    Axilox.xfd - not work.
    On this game the emulator takes off with an error.

    breaker - 30 08 09 - 20:18

    phaeron, I have found many images of disks *.dcm, but in your emulator it is not supported.
    Add please in following release of the emulator support of files *.dcm

    breaker - 30 08 09 - 21:33

    Many thanks Phaeron, you changes have made a huge difference, and support for auto tapes, carts and xexs is excellent.

    hardmanm - 30 08 09 - 22:43

    Could you include screenshot capturing in .png format in 320 X 200. The screen capturing in Atari800win makes the images look dark.

    hardmanm - 30 08 09 - 23:00

    Will you be able to add full joystick support

    hardmanm - 30 08 09 - 23:16

    Yes, full joystick it would be magnificent.
    For a long time already I ask, but while чтото it is ineffectual :(

    breaker - 31 08 09 - 00:29

    Cant get any version of bounty bob working on Altirra including the cartridge version.

    hardmanm - 31 08 09 - 01:07

    in 1.3pre 14, game Bounty Bob Strikes Back!.rom - work.

    breaker - 31 08 09 - 01:58

    XL and PAL seems to make the Bounty Bob Strikes back work fine..Not tested all images but so far all do but PAL mode made the difference

    Mclane - 31 08 09 - 05:00

    Bounty Bob rom also works fine

    Mclane - 31 08 09 - 05:02

    Axilol XFD causing crashdump, works with Win Plus..

    Mclane - 31 08 09 - 05:16

    Bounty Bob the rom version dosnt work on mine even with latest beta and using pal

    hardmanm - 31 08 09 - 08:28

    I fixed the bug in the disk handling routine that was causing the emulator to bomb on the Axilol disk image:

    I would like to know if you devoted folks consider this good for a 1.3 final release (because I need to do a real release /eventually/).

    As for individual feature requests:
    - DCM disk format: This is a complex compressed disk format, and good specs aren't available. It'll probably take some time to implement and test this. I have to say that I don't have too many DCM disk images....
    - Joystick: Yeah, yeah, I need to rewrite the whole input system because it's a mess....
    - Screenshots: Don't really want to drag in VirtualDub's PNG engine just for this, although there is View > Copy Frame To Clipboard. It copies out exactly what the display routine gets. One comment, the Atari 800's display isn't 320x200. It's nominally 320x192 for the standard mode 0 screen and it can be as large as 374x240.

    Phaeron - 31 08 09 - 17:41

    Phaeron....Yes a 1.3 release sounds great, it's HUGELY improved over 1.2 so yes..

    DCM should be a fancy last bit add on, it's one of the most under used image formats on the Atari, I'd rather see exe com and bas support along with updates to the cart system long before that. It seems the biggest bug bear no pun intended is the level unsupported bad opcodes..

    Anyway, thanks's looking great!

    Mclane - 31 08 09 - 20:15

    Phaeron, a question re the Yogi / Jellystone mega images, now I used these a lot in the day and I swear whatever was on them worked but under Atari800win, A800 and Altirra I get the same issue, some games boot and work, sometimes the game seems to hang and gets stuck at $F6ED where it loops forever or the game seems to load ie there is I/O but it returns control back to the menu disk where you can try and load another game but normally it locks up after a few goes as I presume it's losing ram?

    I've tried all settings but no joy and I swear the images were fine in the day...

    Sorry, I've got no real hardware to try these on now, I used the loader disc and games menu 1 in D2: and tried Z...

    Mclane - 01 09 09 - 04:08

    Sorry, had mixed hardware and firmware so the address may be around the $F200 area in XL mode

    Mclane - 01 09 09 - 04:11

    Phaeron, I spread all the images *.dcm which to me it was possible to find.

    And what such difficult in loading *.bas files?
    I understand there simply must include basic and loading the program, then made the team launch and all.
    Or I am not right?

    Today played games River raid and Star raiders II.
    It seemed to me that in these games a wrong sound.
    I mean a sound (noise) of work of engines.
    In emulator Atari800WinPlus 4.0 this sound is a little another.
    Where should sound correctly in altirra or Atari800WinPlus?

    breaker - 01 09 09 - 05:00

    Phaeron, my apologies, I never noticed you had added all the various images as bootable directly from a command line, even carts and com files...Marvellous!!

    Mclane - 01 09 09 - 06:09

    $F6E2 in the OS-B ROM is the keyboard wait routine, which strongly suggests that the game is actually waiting for input....

    BASIC files are annoying to load because there is no easy interception point. Consider:
    * BASIC loads from CIO, so a CIO device has to be exposed. Disk (D:) can't be used because that requires FMS (DOS) to be loaded. Cassette (C:) is painfully slow. And I wouldn't want to use H: (Hard disk) because that may already be in use. That means I'd probably have to do another CIO hook.
    * Initiating a CIO load is a pain because you have to wait until the disk boot expires, wait until BASIC is at the READY prompt, and then inject keys into the keyboard or the CIO E: handler.
    * Injection into memory is possible, but I don't know enough about Atari BASIC to tweak all of the page zero pointers. It's more complex to load a BASIC program directly than an EXE/XEX, believe it or not.

    For an EXE/XEX load, I simply hook DSKINV to tell when the disk boot triggers, and then punch the data blocks straight into memory. It's about a page of code.

    Checking against a real 800XL, neither Altirra nor Atari800WinPlus 4.0 are very good sound-wise with regard to River Raid. River Raid's engine sound is supposed to sound rather high-pitched and hissy, but the emulators are a bit muffled. It probably has to do with analog effects in the POKEY output path that aren't emulated well. According to the debugger, River Raid's cruise sound is the 17-bit noise generator sampled at 2779Hz. My guess is that the channel output in this case probably more resembles a sawtooth or exponentially decaying pulse rather than the square wave that I'm down-filtering; I have a high-pass filter in the chain, but its cutoff is probably far too low for the effect needed here. Altirra's output path is also not very representative, as I'm box-filtering the 1.79MHz waveform down to 64KHz and then resampling that down to 22KHz. I'm not an electrical engineer, unfortunately, so I can't dissect the filter circuits on the Atari 800 schematic. I suppose if I get bored enough I could try firing pulses out of the 800XL and sampling the impulse response.

    Phaeron - 01 09 09 - 16:57

    Re the mega images, that keyboard wait would make sense if the menu loader was instead of running the game just returning control to the loader. I wish I had a real Atari still to test the case, from looking at the debugger most of the time all that happens is that the loader simply loads the game into ram and then does not initialize it, from the noise it makes and the screen flicker I'm guessing what should be happening is that the loader sets the warm start vectors and does a warm start to run the game code, it's like in a lot of cases it's loading the code and then jumping to a warm start without setting the vectors although I'm most likely a million miles out.

    It's been like an eternity since I coded but lots of menu loaders used that way of starting loaded code as opposed to loading and running from the start header. I know it sounds a bit petty but I'd love for someone with a real atari to test the mega image no.1 and load 1st menu list item Z and see if it works on real hardware.

    Mclane - 01 09 09 - 22:08

    HOLD UP.....

    Just found there's a duff loader disc out there, managed to find another version and bingo, stuff is running, still a few duff files but much more actually works..


    Mclane - 01 09 09 - 22:25

    A bug report:
    When going full-screen (Alt+Enter), the joystick ("keyboard arrows") is always moved UP. After pressing Alt+Enter again (& switching back to windowed mode), the joystick centers again.

    Congratulations on Altirra. Do you plan to enhance the cassette recorder emulation even further (waveform synthesis, tape counter, tape control [rewind/ffd])? ;)

    galu - 02 09 09 - 09:18

    Possible bug in SIO patch?

    Enclosed link to a multiboot variant, don't know the issue exactly, I'm presuming it's just streaming sectors off doing a standard sector read call but if SIO patch is enabled items are not running, Adv Creator plays music but sticks on the menu screen, Pole Position seems to just die.

    If I use burst I/O all is ok.

    Is there any reason the SIO patch could cause this, I'm sure it's an unprotected disk and just running like a standard multi boot type program ie pick choice, read in sectors and run game.

    Any idea's Phaeron..

    Mclane - 03 09 09 - 23:24

    Mclane, an interesting disk.
    I have thought in the beginning that it is a disk from homesoft.

    more errors:

    Barahir (v2).atr - not work.
    Barbarian (v2).atr - not work.

    Phaeron, it is possible to add automatic cold reset after file opening in menu File--> Open Image?
    Then automatic loading, as in emulator Atari800WinPlus 4.0 will turn out.

    Still I very much wish to ask where it is possible to take images of disks *.PRO, I have reconsidered many sites but so anywhere and has not found. :(

    breaker - 04 09 09 - 01:49

    Breaker, Re PRO images, don't expect support for them in any emulator as they are property of Steven J Tucker, the guy who wrote & designed the APE software and lead. Basically they are a fully backed up image of a file be it fully protected or not.

    I've asked Steven many times over the years to allow a dll of the pro system out but he's always declined.

    The idea of the auto reset is good..Hope it gets added....And maybe support of OS-A, I know there's not many programs that use it but it can't be too hard to support that rom image just for emulation completeness.

    Mclane - 04 09 09 - 02:19

    Just to elaborate a little

    The program works but these two images are reported as corrupt so I suspect there's a small header issue..

    Barahir (v2).atr - not work.
    Barbarian (v2).atr - not work.

    Mclane - 04 09 09 - 02:32

    I'll probably avoid working on cassette features for a while, because frankly I hated tape growing up and I don't like it any better now. But hey, I never thought I'd write an emulator, either....

    I've seen some disk images where the menu program dies if SIO patch is enabled because the emulator boots the menu too quickly. In one case, the menu died because it expected at least one vertical blank to pass by while reading sectors, and when that didn't happen, it failed to function because the new display list never activated. This is a bug in the menu program, but it's annoying nevertheless. I'd have to look at this specific case, though.

    With regard to .PRO, Steven J Tucker doesn't have any say in the matter. The PRO format is a very simple format that contains a raw dump of the return from the SIO status command a list of phantom sectors. As far as I'm concerned, he has no moral say because it's an image of someone else's work, and he has no technical say because it's already been reverse engineered by multiple people and both Atari800 and Altirra can boot many PRO images without any of his code. It's also not a proper image because it lacks timing information and doesn't contain enough information to reconstruct the original disk. Anyone who actually wants to create a proper image of a protected disk should use VAPI instead.

    Phaeron - 04 09 09 - 07:08

    Figured out why Mclane's megadisk doesn't work with SIO patch enabled -- it's a bug in Altirra. The menu loader expects the CRITIC kernel flag to be cleared after a disk transfer.

    Phaeron - 04 09 09 - 08:29

    Oh, forgot to mention -- the reason that the Barahir and Barbarian images don't work is that they're not actually ATR images. They have no header and should work in current versions if renamed to XFD. Ah, file format fun.

    By the way, I've released version 1.3 final, so commenting should continue in the new post. :)

    Phaeron - 04 09 09 - 12:56

    Aha re the PRO image, glad you know what it's about, as I say I had asked him many times as I thought he had some sort of intellectual ownership of the code or some such. Roll out the VAPI support ;)

    Glad you sorted the mega disk I sent, I just could not understand why as it was technically only transferring data rather than running a protected disk check that it would not work.

    Mclane - 04 09 09 - 18:01

    Just had a good play with 1.3 and it's looking sweet, yet another superb set of updates, the last few versions have actually got me getting out my beloved Mapping The Atari and actually playing around with some code for old times sake.

    Mclane - 04 09 09 - 18:35

    Phaeron, re OS-A, do you think you will add it or just leave it to the Translator XL disk?

    Mclane - 04 09 09 - 18:52

    Realistically speaking, even if Mr. Tucker did put out a DLL, no one would use it. Most emulators are GPLed and couldn't use a closed-source library (the VAPI DLL is also problematic for this reason). Even if that weren't the case, I think most emulator authors would still rather have format specs.

    OS-A support is easy to add, but I didn't want to get in a cycle of perpetually putting off 1.3. If you want to try something on OS-A, you can simply rename the OS-A ROM image to atariosb.rom and it will work. I'm curious if there is anything that requires OS-A since I've never heard of that and the only difference is bug fixes. It's way different than the OS-B / XL situation, where there is a lot of software that is incompatible with the XL ROM but has no problems with the XL hardware (which you can verify with the Translator disk).

    Mapping the Atari is probably the most awesome must-have book for the Atari 8-bit series, especially the updated XL edition. Its presentation of the kernel database is far more usable than the OS Manual. I highly recommend keeping a link to the online version so you can search it.

    Phaeron - 04 09 09 - 22:59

    Perfectly :)
    Many thanks Phaeron, for the new version of the emulator.

    That I wait in the following pre-relese:

    1) additional options joystick №1 and №2

    2) save states (not Quick save)

    3) support of files DCM and BAS.

    4) OS-A and possibility to load others OS.

    5) automatic cold reset at loading of files through menu File-> Open Image

    breaker - 05 09 09 - 01:20

    I'm lucky enough to still have my original revised XL XE edition here, it was my bible in it's day. It's a bit yellow now but that's it.

    Not really worried about OS-A, there's a handful of games that seem to use it but for those there is an OSA boot disk. As regards renaming, I already renamed the XL rom so I could use my Omnimon dump..Works well.

    Was surprised no one asked for .atz image support, don't worry, I'm not asking for it as all the atz images are already in collections as their unzipped atr version.

    Was nice to see the pro images actually doing something for once although the vapi stuff is way more popular.

    Mclane - 05 09 09 - 01:21

    @Breaker, Hi there..

    Just a question, why do you want save states as opposed to quick loads and saves, apart from having the ability to do multiple saves I can't see a difference?

    I had toyed with the asking for a loadable alternative OS, as you have just read I load Omnimon instead of XL for most things so it would save the naming back and forth.

    Mclane - 05 09 09 - 01:26

    Phaeron, one of the users on the Atariage forum did mention something I'd noticed but his was way more detailed.

    His post.

    This is well on the way to being my favourite Windows emulator. Can't use it for development work, however, until the key mappings are completed. It's a bugbear with many emulators, and easily overlooked: many shift+ctrl key combinations (including shift+ctrl+number key/up and down cursor) aren't implemented

    Mclane - 05 09 09 - 01:30

    And my last couple of suggestions after emulation based fixes get bolted down, 2 simple (I hope) idea's..

    1. Drag and drop

    2. Silly but a built in SAP player?

    Mclane - 05 09 09 - 01:45

    Mclane, hi.
    quick save inconvenient if game big enough that I can spend a lot of time for passage but and not reach the end.
    And later, if to restart the emulator, quick save have disappeared also to me anew it is necessary to pass all?
    And if I write the program, to me too after each restart of the emulator to make a fresh start?
    I any more do not ask preservation in a kind *.a8s but if it is possible quick save to keep in the form of a file, make it, please!

    breaker - 05 09 09 - 01:53


    Recently I've found an interesting site about Atari turbo formats used
    in Czech, Slovakia and Poland. Author of this site (Michael Kalous)
    created a TURGEN SYSTEM and libataricas library. At this moment the
    program supports all the Czech and Slovak turbo systems and two Polish
    systems (KSO Turbo 2000 and Turbo 2000 F). What do you think about
    adding these functions to Altirra? :)

    And of course both links:


    voy - 06 09 09 - 05:46

    I'd have to look into it some more, but it already looks pretty annoying since the turbo loaders require a hardware modification to the cassette that allows the FSK decoder to be bypassed. That means I'd have to change the way that the cassette tape is stored in memory, since right now I decode it from FSK on load and that isn't possible if the command line can be used to tell the tape to selectively decode portions.

    Phaeron - 06 09 09 - 21:24

    Isn't that straying away from emulating the Atari just a step too much at the mo?

    It's a nice idea but getting the em more friendly and correct should come first?

    Mclane - 06 09 09 - 22:44

    1. The joystick bug in full-screen mode hasn't been fixed (1.4pre1). Tested under Win7 x64 and WinXP SP3. By the way - if anyone wants to use Altirra with joystick or gamepad right now, there's a little freeware utility called Xpadder that helps to map keyboard keys to gamepad/joystick buttons/directions.
    2. Altirra has very nice color palette by default (unlike all other Atari 8-bit emulators in past 15 years ;) ), and that includes border artifacts colors. But are you going to add custom palette support in the future? Or some fancier filters like Blargg's NTSCFilter ( )? Just out of curiosity - I hope that there's not too much pressure from the userbase, but Altirra is really shaping up to be the ultimate Atari emulator ;)
    3. Suggestion: It would be nice to have an "Autoboot image" option in File menu.

    There are some usability problems, like Altirra opening with empty window by default, but I'm sure that you are aware of them ;)

    Great work!

    galu - 07 09 09 - 02:38

    Well, it seems that Xpadder is not freeware anymore:
    "As of Apr. 29th 2009 XPadder v5.4 is available as payware."

    galu - 07 09 09 - 03:00

    you can still get the free version from

    hardmanm - 07 09 09 - 19:29

    Phaeron (or Anyone)

    Do you know of a program that will look at the first couple of bytes of a file and if they equal what I want either print the file name or move the files to another directory. The reason for this query is that some fool added their collection of .com files all together. Sadly it's mixed between PC and Atari .com files and the file sizes are small so I can't sort on that basis. The one thing I've found out is that the Atari files start with "˙˙" so I can run a compare bit of software but they all seem to read the whole file in and find that combination of bytes in a lot of files.

    Hence I'm desperate to just read the first couple of bytes and either list or move the matches..

    Any idea please?

    Mclane - 13 09 09 - 00:26


    Mclane - 14 09 09 - 05:58

    Is there an new beta due out soon to test with my gamebase

    harmanm - 14 09 09 - 08:45

    altirra 1.4 pre3 and discussions here.

    breaker - 14 09 09 - 12:53

    Comment form