Re: The Soundblaster DSP project

Posted on 2023-10-13, 20:49

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by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

can be the ultimate MPU solution. any thoughts on this, i.e. stand-alone 6801-emulator or maybe even board with 6801 controller that can execute the original Roland MPU-401 ROM: https://www.vogons.org/viewtopic.php?f=62&t=96744 again, I know noting on the subject and thus my ideas could be very …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 20:22

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by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

@mkarcher thank you for the excellent explanation and one more time big thank you to @Cloudschatze for all the invaluable (at least to me) information provided on the MPU-401 Intelligent mode command and all. saying in one foreign (to me) language -- Chukcha is not reader, Chukcha is writer. I am …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 20:12

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

To @mattw, you miss one thing - MPU dataflow is controlled by 2 bits in MPU status register (0x331) So you cannot read MPU data port, until Status port shows that data is present in data register. yep, it seems that way, using 'Debug.exe' for the test - i shouldn't do '-o 331 ac' and then …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 20:06

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by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

By checking the DSR status bit from the Command port thanks, I believe I maybe finally got it (as low IQ as I am): I am judging for ACK by the value of IOPort 0x330 (which is let's call it the 'new way'), but there is 'legacy way' with checking the DSR status bit (bit 7) in the value of IOPort …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 19:41

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by mattw

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, 19:07

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by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Not sure about this. Need to check it with HardMPU source code )) at least I got totally lost now - I mean what those known "Fake ACK" cards do more then? I mean as far as I understand from what @Cloudschatze wrote and based on my test results, the "Fake ACK" cards transmits electrically out what …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 18:51

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

DSP can only be brige for midi data. it seems we were writing again at the same time - please, see my post above yours. Exactly, but SysEX messages are considered MIDI-Data and not commands, correct or not? and cannot send it to MIDI OUT. what you were sending out and how you were sending it out …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 18:47

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I am away over my level of knowledge and understanding, but thinking more about it - maybe the "Fake ACK" cards, actually not just ACK all commands (written to IOPort 0x331) and send them all out electrically on the connector, but only send out the commands that are SysEX requests, aren't those have …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 18:25

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

What problem do you want to solve with this ? it seems we both were writing at the same time. essentially, what is needed is Commands written to IOPort 0x331 that are not really acknowledged (they look like acknowledged based on the value in IOPort 0x330, but that is just left-over from the …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 18:16

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by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

or maybe even simpler - "residual" ACK doesn't matter and just patch the DSP code, no matter if there is Real ACK or not - always output electrically to the DB15 connector the SysEX.

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 18:02

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

@Maelgrum : based on the above findings do you think you can as 1st step mod V4.13 to not leave any "residual" ACK, i.e. after 0xFE is in the IOPort 0x330 Xreg and the register is read, set its value back to 0xFF (or to 0x00 - I am not sure which one is the correct to remove the ACK) or something …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 17:57

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Looks like the MPU is either uninitialized, or just needs to be reset first (0xFF), after which the output should match what you saw for the AWE32. The "FE" byte that you're reading back in this case isn't an acknowledgement of the prior commands. It's residual. you're correct on CT4170 DSP V4.16, …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 17:42

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by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

SB16's MPU still won't accept/transmit MIDI data outside of UART mode, which is the other piece necessary to match the behavior of the Ensoniq and Audiotrix Pro cards. I see, that is good explanation. So, nothing comes out of the DB15 connector as electrical signals on SB16, but it goes out on the …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 17:19

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

You won't get any response to, or acknowledgement of, the version/revision request. the things are now getting real unexpected turn, because the above is true, but for my CT4170 DSP V4.16 card (which as Build-in MCU in the main chip cannot be modified anyway) and here is how the test looks: C:\> …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 16:52

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Maelgrum wrote on 2023-10-13, 16:45: IO 330 is bidirectional, of course. OK, let me test this same thing: Re: Roland LAPC-N / I question on my AWE32 and see how it looks like - maybe that will help us imagine the things better... be back in 10-15 minutes with the results.

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 16:42

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

No luck - looks like x-regs are in range 0x00-0x1F , and 0x80-0x83 (ASP/CSP). I made X-Regs dump on CT4170 with DSP V4.16 and then your statement becomes real obvious, because: 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F -------------------------------------------------------- 00000000 00 00 BF …

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 16:26

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Maelgrum wrote on 2023-10-13, 16:08: If any 0xAE byte is found in xregs.bin - its a good sign see the attached dump - 0xAE is there - I hope it's also on the right place and not some other 0xAE....

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 16:01

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Maelgrum wrote on 2023-10-13, 15:54: Byte written to IO port 0x331 - x-reg is unknown, and maybe not exists. Testing is needed )) thank you, if you come up with a test procedure - let us know - I am sure here are more people, than just me, always ready to help and test with whatever they can.

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Re: The Soundblaster DSP project

Posted on 2023-10-13, 15:49

by

by mattw

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

read from x-reg 0x02 I guess my question is (if I am not totally confused and mistaken) : which 'x-reg' register corresponds to the content written to IO Port 0x330 and which one to 0x331? isn't for the "Fake ACK" sufficient just to always return 0xFE to IO Port 0x330, no matter what was requested …

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Re: MAME Roland MPU-401 Emulator

Posted on 2023-10-13, 12:34

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by mattw

in Marvin \ Sound

in Marvin \ Sound

I don't know which is the best way to disassemble 6801-assembler, even less I know how to read it, but even my very clumsy attempt , seems to make a lot of sense: mpu401_asm.jpg because MPU-401 Command 0xAC and Command 0xAD communication is the following: https://www.vogons.org/viewtopic.php?p= …

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