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HardMPU, anyone?

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Reply 60 of 608, by alexanrs

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AFAIK even UART MPU interfaces should recognize the RESET command and return an acknowledgement signal. Not every sound chip manufacturer obeyed that, though.

Reply 64 of 608, by ab0tj

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Some parts are starting to show up. This project is starting to exist in the physical world now!

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Reply 65 of 608, by ab0tj

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The ISA prototyping board finally arrived last night. Shipped from Thailand, no wonder it took so long. I soldered some pin headers to the ISA signal area and wired it up to my breadboard. After correcting the order of the address lines, I can at least cause a MIDI program to lock up. Previously it was just "could not initialize sound hardware". I think something is wrong with either my code or my wiring as the status bits are not being reset. More debugging tonight as time allows. But at least it's progress!

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Reply 68 of 608, by alexanrs

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If all the connections are fine (protoboards can be evil) and you are convinced that this is a software issue, we could try helping you if you are willing to share the code.

Reply 69 of 608, by dr.zeissler

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I would REALLY need such an MPU-401i-Card BUT can it be multifunctional ?
Most old machines do not have many ISA-Slots, so Cards like a "VGA-Blaster VGA+Soundblaster", or "JUKO G7B EGA+Multi I/O" are very rare but unsefull!

I need a MPU-401 Interface combined with either:
- VGA Card (1MB)
- EGA Card (256KB 8Bit)
- Multi I/O (8BIT-Card)
- Soundblaster (CT1350b like)

My A2000 Bridgeboard A2286 could be used beside the Amiga Part for covering all the old dos stuff,
but the Problem is, there are only 3 ISA Slots (Soundblaster and MPU401i are safe), but what about VGA/EGA, what about SCSI, IDE, Multi I/O ?

Doc

Retro-Gamer 😀 ...on different machines

Reply 70 of 608, by ynari

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An Amiga bridgeboard is somewhat of a special case, actual PC motherboards aren't short of slots. Pentium 4 boards tend to have only one ISA slot, with a p3 it was usually one ISA, one shared PCI/ISA, but that's not an issue as the remainder of cards were PCI/AGP. Prior to the pentium 3 there's usually lots of spare slots.

You may be able to extend your bridgeboard's ISA slot count with appropriate hardware. There's probably an Amiga hacker who has done it..

Reply 71 of 608, by ab0tj

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alexanrs wrote:

If all the connections are fine (protoboards can be evil) and you are convinced that this is a software issue, we could try helping you if you are willing to share the code.

It's mostly due to the fact that the code I wrote for testing was just a quick and dirty UART only implementation. As I have time to debug things, it is getting better. The MIDI playing program now thinks it is working after I found some code problems. I just need to hook it up to an actual MIDI device tonight and see if anything comes out. I will definitely be sharing the code, but it's not worth sharing yet.

dr.zeissler wrote:

I would REALLY need such an MPU-401i-Card BUT can it be multifunctional ?

Unfortunately that is beyond the scope of this project. Maybe after I have a functioning device, I can look into adding serial and parallel ports. Making it a video card or a full-fledged sound card are beyond my skillset at this point, but maybe someone here that knows FPGA's could come up with something.

Reply 72 of 608, by alexanrs

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dr.zeissler wrote:

I would REALLY need such an MPU-401i-Card BUT can it be multifunctional ?
Most old machines do not have many ISA-Slots, so Cards like a "VGA-Blaster VGA+Soundblaster", or "JUKO G7B EGA+Multi I/O" are very rare but unsefull!

If you have the means to, you could take a look at this project and, when either this is finished, join both schematics and make a new custom board for yourself with both devices, using one of those brackets with two RS232 ports (DB-9 and DE-9 have the same external dimensions).

Reply 73 of 608, by ab0tj

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Success! After some software debugging, I now have a working UART implementation on a breadboard. Now to start porting the intelligent part.

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Reply 74 of 608, by alexanrs

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Hurray! Glad to see this project advancing so well. This should be a very easy project for an end user to build since its only an AVR and glue logic, and the schematics should be pretty much final, since all that is needed for the intelligent part is the software aspect =)

Also, please edit the first post with the current schematics, info and, if you feel its worth it, the firmware. As the topic grows, it might be easier for new people to catch up to whats happening with the first post instead of reading through the entire thing.

Reply 75 of 608, by ab0tj

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More success after some coding today. I now have intelligent mode working! It was pretty much just a dirty hack job of porting SoftMPU, but I have successfully tested with Silpheed. I still need to investigate some stuck notes and glitching, though. The firmware definitely isn't done yet. More debugging tomorrow as time allows.

You can check out the current code here: https://github.com/ab0tj/HardMPU/

Reply 76 of 608, by alexanrs

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You could always try to revert it to UART firmware (or perhaps have a jumper to enable/disable intelligent mode for testing) and use SoftMPU and test the game to see if the hanging notes and stuttering are caused by your own intelligent MPU code.

Reply 77 of 608, by stamasd

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I will buy 2 boards when you have them available. Can also be in kit form, or even bare PCB. I'm skilled with a soldering iron (even SMT 😀)

I/O, I/O,
It's off to disk I go,
With a bit and a byte
And a read and a write,
I/O, I/O

Reply 78 of 608, by dogchainx

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So how would this interface to external MIDI (MT32, etc)? Joystick/midi-type port?

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Reply 79 of 608, by alexanrs

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Well, once you have the serial data lines you can make whatever connector you want. Using a DB-9->dual DIN-5 like keropi's MIDI card clone would probably be a good idea (as you can reuse brackets used for serial ports.