Re: SBEMU: Sound Blaster emulation on AC97

Posted on 2023-10-14, 13:08

by

by georgel

in Marvin \ Sound

in Marvin \ Sound

dj_pirtu wrote on 2023-10-14, 12:49: Thinkpad T42p and no sound so far. Tried demoscene: Verses and Drift, both don't detect sb pro and crash if forced. Next I'll try games. Don't have DOS/Win98 yet on this so booting from floppy. Have you checked if there is sound at headphones connector?

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 20:20

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

anyway, I hope, at least those of us that didn't know anything about that subject - learned something new. It is not new -- it is in the widespread vintage SB manual I posted link to in my previous message. But there is a saying in one foreign (to me) language -- Chukcha is not reader, Chukcha is …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 19:45

by

by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

This may help clarify: https://www.vogons.org/viewtopic.php?p=588674#p588674 thank you very much, it helps, but it brings me back to the very beginning of the discussion: I see "0xFE" Acknowledge on the tests I did on my AWE32 DSP V4.13 card, even further tests with DSP v4.16, clearly revealed that …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 18:40

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

While 3x1h port address seems not operational for writes there are other port addresses that are available and moreover during UART mode are almost useless. So if you can figure a simple way to divert 3x1h MIDI commands to one of them either in software on PC side or in hardware on SB (like some PNP …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 13:52

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thinking about intelligent MPU mode, there is a problem - current fw not uses MPU command register at all. All it uses, is one signal line from Bus interface chip, telling what MPU Uart mode is running, or not. So questions - is MPU command register present on x-bus (but not used) Is any bit flag …

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Re: The Soundblaster DSP project

Posted on 2023-10-11, 20:42

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thanks to all members for testing. Results are mixed, and strange. What tools are you using for debugging the DSP firmware? Mind. Pencil and paper. Tea. Disassemler - D52, code editor - visual Studio code, compiler - keil, but for _debugging_ - don't know any tools, except mentioned above)) Too bad …

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Re: The Soundblaster DSP project

Posted on 2023-10-11, 20:21

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Maelgrum wrote on 2023-10-11, 20:10: Thanks to all members for testing. Results are mixed, and strange. What tools are you using for debugging the DSP firmware?

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Re: The Soundblaster DSP project

Posted on 2023-10-11, 19:47

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

1,2,3 play with clicking at the end of buffer I guess . 4,5,6 click at the beginning and no more. Tested on vibra16 and on CT3900 with discrete DSP. No difference. For me this sbplay.exe worked only under QEMM. Otherwise used to halt and produce no sound , nor console output. But the latter is not a …

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Re: The Soundblaster DSP project

Posted on 2023-10-11, 10:07

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

A frequency of 33MHz at which AT89S52 is guaranteed to work will do fine for the test I am proposing. Previous test build of fw (with significantly lowered execution time of cmd 0x14 and End of block ExtInt1 interrupt) shows no audible difference on clicking (compared to classic 4.13). I suspect …

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Re: The Soundblaster DSP project

Posted on 2023-10-11, 07:03

by

by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

A frequency of 33MHz at which AT89S52 is guaranteed to work will do fine for the test I am proposing.

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Re: The Soundblaster DSP project

Posted on 2023-10-11, 06:44

by

by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

For testing of theory that latency of DSP is related to single cycle DMA clicking why don't you overclock the DSP to some extent by replacing its crystal (the newer MCUs will even not be overclocked in relation to their maximum clock frequencies) or providing an external clock (from oscillator)? …

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Re: The Soundblaster DSP project

Posted on 2023-10-11, 05:52

by

by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

For testing of theory that latency of DSP is related to single cycle DMA clicking why don't you overclock the DSP to some extent by replacing its crystal (the newer MCUs will even not be overclocked in relation to their maximum clock frequencies) or providing an external clock (from oscillator)? …

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Re: The Soundblaster DSP project

Posted on 2023-10-10, 17:17

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Anyway 4.16/4.13 firmware plays without DMA clicking on all SBs with integrated DSP so this problem is not a matter of firmware but of hardware.

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Re: The Soundblaster DSP project

Posted on 2023-10-07, 08:55

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

... Most compatible will be classic 24MHz mcu. If only thing what wanted is cure for single cycle dma bug - existing fw can be patched to significantly reduce execution time of critical parts of code. It may help. Or not)) Had it been a firmware bug only 4.16 would have corrected it, because cards …

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Re: The Soundblaster DSP project

Posted on 2023-10-06, 17:34

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hmmm... I wonder if it's possible to configure the 8052 to run in faster modes (6T or even fewer clocks per cycle) for the DSP code, if supported. If the DSP code itself contains nothing requiring complex delays then it might work out okay, allowing the execution path to finish a bit faster to meet …

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Re: The Soundblaster DSP project

Posted on 2023-10-06, 16:45

by

by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Keep in mind we are not sure at what clock an integrated 8052 is running.

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Re: The Soundblaster DSP project

Posted on 2023-10-05, 20:57

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Older versions of FW (less than 4) AFAIK do not have functions F9 and FA, without them, this method of dumping does not work.

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Re: The Soundblaster DSP project

Posted on 2023-10-05, 16:50

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

sb16dump V0.17 support for v4.12 Now since no new firmware will be released by Creative, the fun with dumping can only continue with clone cards. On the other hand have you checked how 4.16 is fixed against hanging notes bugs? Looks the most proper way to improve the firmware is to make fixes on 4. …

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Re: The Soundblaster DSP project

Posted on 2023-10-05, 16:02

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by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

maxtherabbit wrote on 2023-10-05, 15:51: I do not have the ability to disable NMIs on this board short of putting a piece of tape on the card edge or something Yes , tape would work perfectly. It is the rightmost pad on the XT edge connector but I guess you know that.

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Re: The Soundblaster DSP project

Posted on 2023-10-05, 15:29

by

by georgel

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

maxtherabbit wrote on 2023-10-05, 15:27: Maelgrum wrote on 2023-10-05, 15:08: sb16dump V0.15 experimental support for 4.12 (found error in previous version) This triggered an NMI for me on my AWE32 I guess it jumps to a code which generates NMI for MIDI emulation with AWEUTIL.

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