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Altirra 2.80 released


phaeron

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The support for multiple drives also means that Happy Multi Drive works

 

I always though that Happy Multi Drive was an amazing and under estimated feature. Most of us never had any need for something like that. But wonder if some company used it for in house disk duplication?

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I always though that Happy Multi Drive was an amazing and under estimated feature. Most of us never had any need for something like that. But wonder if some company used it for in house disk duplication?

 

Perhaps a very small operation. Anyone who needs to distribute much of any kind of volume I'm guessing would use professional duplication or professional duplication services.

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Perhaps a very small operation. Anyone who needs to distribute much of any kind of volume I'm guessing would use professional duplication or professional duplication services.

 

Depends on the period. At later years, say, the 90's, mass duplication services were so widespread and affordable. But during earlier years it was quite common to duplicate in house. Volume production was rather small yet industrial duplicators were too expensive.

 

Many of the most heavily protected original Atari 8-bit disks were duplicated in house. Don't know if any publisher actually used Happy drives with standard Happy Software. Obviously that couldn't be the case for the most advanced protections. But for more "simpler" protections, can't rule out somebody used standard Happies.

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Not so much a bug as a 'feature', I found when using an emulated US Doubler asa device that if I switched from PAL to NTSC then it stopped booting disks, even if you turned off the emulator and restarted it. I found that if I put the screen back to Pal then it happily booted stuff with an initial short hesitation. I tracked it down to having Fast Boot enabled under System / Acceleration. Turn it off and all is well.

 

Just in case people do that utterly random thing I did while testing, I wondered what the hell was wrong, all I'd done was switch country video, and when it would not work after a full emulator power down I thought I'd reset the settings but decided to track it down instead.

 

Paul.

 

EDIT: There are mentions from Phaeron in past posts about fast boot interfering with some boot procedures, I just missed these but at least there's now a recent post after after all these wonderful emulated drives have been added wwhich may save some searching. Not sure why a change of video source would affect apart from timing differences..Pass, what do I know :)

Edited by Mclaneinc
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Yes, Fast Boot can make the computer boot too fast. One way to think about it is that Cold Reset flips the power on a power strip that has the computer and drives plugged in and already turned on. With the normal drive emulation, the drives can be online immediately; with real drive emulation, the firmware may not be able to finish init quickly enough. I've seen some firmwares take so long that even with Fast Boot off they still may miss the entire boot sequence. The SIO bus is set up so that devices can tell when the computer turns on, but not the other way around.

 

For now, the workaround is to enable Ultimate1MB and use its soft-reset to reset the computer without resetting the drives (Help+Reset, then reboot through the BIOS). This is also how you can test the Happy tracer. Long term I need to put in reboot-computer-only and/or a startup delay option.

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  • 2 weeks later...

Disk Drive Saga continues:

 

http://www.virtualdub.org/beta/Altirra-2.90-test27.zip

http://www.virtualdub.org/beta/Altirra-2.90-test27-src.zip

 

Adds ATR8000 emulation -- tested with 3.02 firmware. Took longer than I expected due to an unexpectedly crappy schematic (who needs to label crystals or chips?!) and the need to emulate the weird Counter Timer Circuit (CTC) chip. Unfortunately this particular disk drive has a very long init sequence, so the computer will basically always time out before the drive is ready; use Ultimate1MB to do a "lukewarm reset" so the computer reboots without the drive also resetting. Also, as noted in the SDX4.48 thread, you will have serious issues getting this drive to work under SpartaDOS X due to some questionable density detection and command handling logic. CP/M should work if you can get an appropriate disk image, but I was unable to test it. 8" drives are supported, though you may have troubles loading the disks from .ATR images due to conflicts between 5.25" and 8" formats (some 8" formats look like 5.25" enhanced density, but in FM). RS-232 and printer are not supported.

 

Some bugs in the Z80 core were also fixed, which also affects Indus GT.

 

Some miscellaneous facts about the ATR8000 hardware and firmware:

  • 5.25" and 8" drives are distinguished by whether they rotate at 300 RPM or 360 RPM.
  • SIO transmission is entirely interrupt driven -- even individual bits! I don't know why they bothered, because the interrupt routines don't save/load registers or swap register banks, so it's not like the Z80 can do anything else anyway....
  • The hardware can run with a faster data clock than any other Atari-compatible drive I've seen yet, 1us/cell MFM if I'm reading the schematic correctly.
  • Motor control is unconventional -- it's driven off of the head load signal from the FDC.
  • Motor spin-up delay is rather long in the firmware, 6 rotations. It's probably a bit longer in real hardware since Altirra doesn't integrate spin-up and spin-down ramps.
  • Weirdness with the FDC clock: The XF551 compensates for its drive running at 300 RPM rather than 288 RPM by clocking the FDC 4% faster, but it's not clear if the ATR8000 does so or not because the schematic doesn't label the clock crystal. If they did that, though, then it would make the ATR8000 subtly incompatible with other CP/M systems. On the other hand, if they used standard clock speeds, it'd have difficulty writing to Atari disks instead. Anyone know what the master clock is?

 

 

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Triads, I re-edited the link when I tested the links, the link NOW is 100% ok...Read the edit :)

 

But thank you for making sure K1W1 got the files :)

 

I love this place, every one helps...Seriously, people look and bother to take the time to help rather than just waiting for others to do it..its what makes this community..

Edited by Mclaneinc
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The hardware can run with a faster data clock than any other Atari-compatible drive I've seen yet, 1us/cell MFM if I'm reading the schematic correctly.

Weirdness with the FDC clock: The XF551 compensates for its drive running at 300 RPM rather than 288 RPM by clocking the FDC 4% faster, but it's not clear if the ATR8000 does so or not because the schematic doesn't label the clock crystal. If they did that, though, then it would make the ATR8000 subtly incompatible with other CP/M systems. On the other hand, if they used standard clock speeds, it'd have difficulty writing to Atari disks instead. Anyone know what the master clock is?

 

I don't think they compensated with the clock. The oscillator outputs 16 MHz, and it's divided down to 4 MHz for the master clock, and 2 MHZ (8" drives) or 1 MHz (5.25" drives) for the FDC.

 

The faster bitrate is needed for 8" drives that have a 500 KHz bitrate. If you mean 1us cell for the half bit cell, then it is correct. Bit and minimum flux transition is 2us though.

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Not really a bug and may just be Windows itself..

 

If you are using Warp mode say to speed up a long intro and for some reason a program crashes then warp mode stay enabled until you press F1 again, noticed it on the last beta but may have been earlier, does this on both 64 and 32.

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