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HardMPU, anyone?

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Reply 241 of 608, by stamasd

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keropi wrote:

^ dead ATMEGA? could be! Settings are OK with the same values so that's not the problem 101%

Unlikely, I used 2 separate chips bought from 2 distinct sources. Also like I said, when a game with MT32 support is running I can see a signal on the card's output pin. I cannot determine the conformity of the signal to MIDI standards though because of the lack of sophistication of my oscilloscope. 🙁

ab0tj wrote:

Does the MT32 display show "HardMPU" when you power on the computer? If not, we at least know the issue lies between the Atmega and the MT32.

No it doesn't. The display on the MT32 never changes from the default "1 2 3 4 5". The MT32 itself functions fine: if, while leaving everything else exactly the same, I substitute keropi's MQ clone for the HardMPU card, music in games plays fine on it.

ab0tj wrote:

Also, does the DOS config util work? That would verify successful comms between the host and the Atmega.

I haven't tried it yet.

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 242 of 608, by ab0tj

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stamasd wrote:

I haven't tried it yet.

Based on the fact that you see a signal at the MIDI output, it sounds like it is at least trying to work. But running the config utility would verify that.

Is there still a good looking signal at the MIDI connector with the MT32 attached? Possible you installed a 220k instead of 220 resistor in the interface section or something like that?

Reply 243 of 608, by ab0tj

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For reference, here is what the MIDI signal (at the MIDI DIN plug) looks like on mine. Not sure if it will help any in verifying the baud rate?

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Reply 244 of 608, by stamasd

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From that picture I see that the narrowest pulses are about 1/3 of the 100us division, which is consistent with the midi rate of 31250 bit/s. Unfortunately my oscilloscope can't capture screens like that. I could try to determine if I've got the correct rate if I found something that can generate a regular signal through the MPU401, say a succession of 010101010 or so. Perhaps playing a custom MIDI file.

Also, I'm still tied up with job-related stuff (I'm at work right now).

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 245 of 608, by iKarith

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My understanding of this (for folks who are joining late and haven't skimmed through 13 pages) is that this is an effort to create an ISA card compatible with the real Roland MPU-401 interface, including with the intelligent mode needed by some games to use with the MT-32 and other such devices.

For many uses, a SoftMPU TSR does the job, but for a few things that require a bit too much juggling to make the memory work out, an actual hardware replacement is desired. Makes sense.

A prototype has been built, but it's not working quite yet, boo... 🙁 But it's very promising when the right folks playing with it get a chance to sit down and sort it all out, yay! Nobody's talking about producing boards yet.

... This is all relevant to my interests! 😀

Reply 246 of 608, by ab0tj

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Mostly correct 😀

There's 4 prototype boards so far. Two working, one not, one unbuilt. There will probably be a run of boards once those last two are working and any necessary changes made.

Reply 247 of 608, by cyclone3d

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Ooooh. I just saw this thread. Very interesting and I may be interested in one of these boards.. or in making one of these boards.

Yamaha modified setupds and drivers
Yamaha XG repository
YMF7x4 Guide
Aopen AW744L II SB-LINK

Reply 248 of 608, by RJDog

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ab0tj wrote:

one unbuilt.

So I finally had a couple of hours and built a thing 😎 still totally untested at this point, but at least completed assembly is a step in the right direction.

I used a male D-Sub 9 connector rather than a female as was called for so that the pin 1 would line up right. I have to make a custom cable for it anyway so I figured it was just as easy to use the female connector on the cable side.

Also, don't mind my "fuse". Other than that I think it looks pretty neat. I know the purple is the default OSH Park thing, but it is a cool aesthetic nonetheless.

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Reply 249 of 608, by iKarith

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I'm hoping that once the prototypes are all built/tested, perhaps these can be sold fabricated rather than as kits. That'd probably mean a switch to SMT parts and a new board layout, but at least it'd e established that the design works by then. I can't solder a board like this to save my life (with my eyes? 🤣... You'd be surprised some of the crap a legally blind guy can accomplish, but soldering ICs isn't one I've mastered yet..)

I for one _like_ the purple. I vote for purple for finished boards--kit or otherwise. 😁 So purrrrrrple...

Reply 250 of 608, by ab0tj

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Figures, purple seems to be the one color Seeed doesn't offer. I'll have to shop around when ordering boards.

I don't know about getting assembled units manufactured, there likely won't be enough demand. I could probably solder some together myself to offer for sale, though.

Reply 252 of 608, by Scraphoarder

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ab0tj wrote:

Figures, purple seems to be the one color Seeed doesn't offer. I'll have to shop around when ordering boards.

I don't know about getting assembled units manufactured, there likely won't be enough demand. I could probably solder some together myself to offer for sale, though.

Where can we sign up? My soldering skills are none and could rather work overtime to buy a finished one 😊

Reply 253 of 608, by ab0tj

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Scraphoarder wrote:

Where can we sign up? My soldering skills are none and could rather work overtime to buy a finished one 😊

No signup just yet, this is still in "beta".
Watch this thread for more 😀

Reply 255 of 608, by RJDog

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ab0tj wrote:

Any progress on the test boards? I have been using mine still without issue 🤣

Well, I finally had some time to install and test the board (after nearly forgetting to flash the Atmega with the firmware), and.... very successful!!! Setting it to IRQ 2, 330h, it just worked... no muss, no fuss. The config program worked as excpeted, and all games I have tested so far have worked exactly as they did with the "MPU-401" interface on my SoundBlaster (which I have removed while testing this). Now, the unfortunate part is I don't think I have any games that actually use the Intelligent mode...

https://soundcloud.com/richard-chute-45223942 … hardmpu-usbmidi

Very well done, ab0tj!

Reply 257 of 608, by PhilsComputerLab

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This thought just crossed my mind.

Though the project is based around SoftMPU, have you considered renaming it, or promoting is as simply an ISA MPU401 or simply ISA MIDI card?

Could be a great addition for existing sound cards that have bugs or no MPU401.

Some games to test the intelligent mode interface are Wing Commander, Space Quest III, GODS and of course Gateway.

YouTube, Facebook, Website

Reply 259 of 608, by ab0tj

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So.... It's been a while and there have been no bug reports yet. I guess that means it is time for me to order some PCB's from China. If I were to do so, I'd estimate a bare PCB would cost around $15, $60 for a kit, and $100 for an assembled and tested board. Would there be any interest from the group?

Note that this is not a thread for placing orders, I'm just asking so I can gauge interest.