Berzerkula wrote:

Greetings,

I'll be interested in acquiring a PCB or two. Please let me know if there are some to acquire or a lead time.

I do still have PCBs. Drop me an email at (my username here) @delorted.com

Thanks for sending me the boards. I hope to follow up with my build in a couple weeks.

Greetings,

My inventory has some of the parts and the rest are on order. Right now, I have been having fun programming the ATMEGA1284P with my own programs until I get ready to use it with the HardMPU.

The AVR DIP 40 Programmer by Kamprath I received while working with the Z80 RC2014 and some add-on boards. It works well with the Arduino Uno and IDE 1.8.x as an ISP programmer.

Ready to program the HardMPU.hex soon!

This will be used with the Xi 8088 and micro atx backplane, which I recently was able to enable upper memory blocks!

So I have been testing a new design...

Slap me and call me Shirley. That's a real nice design. I really want to put my Yamaha DB50XG internally sometime so that I won't need to cover another power plug on my power strip (I need to plug in something else into it and it's a pain) or get myself another one for my Pentium 100 system, however, I'm broke AF right now.

HardMPU mk2?! Looking good!! add me to the list of buyers! it would be my second HardMPU!
For whoever is not sure or have doubts about the HardMPU card (previous version): it's an excellent substitute of a MPU-401, even my (real hardware) Win 3.11 and Win95 detects it as a MPU-401 compatible card! ...and of course, all my DOS games including protected mode!
Quality stuff!

I think it'll still be a while before this one is ready for prime time, but it at least works at this point. Now it's time to test, test, test! That's the fun part

Can you summarize the differences?

kolderman wrote on 2020-04-10, 04:36:

Can you summarize the differences?

Sure, there's not a lot.
- Added a wavetable header. There is a CD audio style connector for audio out, to either be connected to a sound card or wired up to a 1/8" audio connector. MIDI output can be switched between the external connector and the wavetable header by software.
- Has a resettable PTC fuse for external power instead of a regular fuse.
- Moved some glue logic into a GAL to reduce the chip count.

Looks awesome! 👍 I really like the audio connector, good idea!

If I may suggest something, could you add some drill holes in the PCB, so that you can use PCB standoffs to securely fasten the daughterboard to the HardMPU? Also, would a full-sized daughterboard like the SCB-55 or DB50XG stick out or is the HardMPU long enough?

Lennart wrote on 2020-04-10, 08:10:

Looks awesome! 👍 I really like the audio connector, good idea!

If I may suggest something, could you add some drill holes in the PCB, so that you can use PCB standoffs to securely fasten the daughterboard to the HardMPU? Also, would a full-sized daughterboard like the SCB-55 or DB50XG stick out or is the HardMPU long enough?

The current design would definitely leave a larger board like the SCB55 hanging off the end. Now that I am looking more into it, the HardMPU might need to be another 12mm or so taller for that to fit comfortably as well. The only wavetable board I have to test with is the tiny Dreamblaster S2. Mounting holes are a good idea, does anyone have a good reference for the dimensions of the holes?

You should find all the info needed from this and following posts :
Re: FMonster, the monster of sound synth

Tiido wrote on 2020-04-10, 14:31:

You should find all the info needed from this and following posts :
Re: FMonster, the monster of sound synth

That does help, thank you! I'm going to do some measurements to see what it would take to do this. I don't think it would increase costs much to make the board larger since it is already larger than the 100x100mm minimum charged by most board houses.

That would be great if you can do that without increasing costs a lot. Daughterboards hanging off the edge is my biggest issue with the Roland MPU-401/AT. It just looks so flimsy.

Just noticed that you mentioned that you can switch MIDI output between the daughterboard and external connector via software. That's a really nice feature as well 😄 Did you hook up the daughterboard to the other serial interface on the ATmega1284, or how does it work?

Berzerkula wrote on 2020-04-01, 17:57:

Greetings, […]
Show full quote

Greetings,

My inventory has some of the parts and the rest are on order. Right now, I have been having fun programming the ATMEGA1284P with my own programs until I get ready to use it with the HardMPU.

The AVR DIP 40 Programmer by Kamprath I received while working with the Z80 RC2014 and some add-on boards. It works well with the Arduino Uno and IDE 1.8.x as an ISP programmer.

Ready to program the HardMPU.hex soon!

This will be used with the Xi 8088 and micro atx backplane, which I recently was able to enable upper memory blocks!

Have the board assembled and the MIDI cable cut in half for IN and OUT. Plan to test soon. Looking good, so far.

Lennart wrote on 2020-04-10, 19:31:

That would be great if you can do that without increasing costs a lot. Daughterboards hanging off the edge is my biggest issue with the Roland MPU-401/AT. It just looks so flimsy.

Just noticed that you mentioned that you can switch MIDI output between the daughterboard and external connector via software. That's a really nice feature as well 😄 Did you hook up the daughterboard to the other serial interface on the ATmega1284, or how does it work?

Exactly, the daughterboard uses the second serial interface. I haven't seen anyone using it for anything else yet, though it could easily be routed out to the connector on the back for an external LCD display or something.

Greetings,

I have been having a heck of a time getting this board to cooperate but I finally have it going. After one magical reboot it started working. Multiple times I've used the MiniPro (two different ones) to program two different 1284P's (which I've used both in a current project) and double checked the fuses multiple times. I double checked all the 74LS logic and all checked out.

After about the 20th reboot and 15th slot change I decided to skip running HARDMPU.COM to see if there was any indication port 330 was working and went right directly to Scott's MIDIPLAY.COM and played ALF.MID with verbose output and walla, my eyes lit up as I saw ativity and heard output from the SC-55. Yippeeee. It does work! My cable works after checking it multiple times.

So another Xi8088 with an NEC V20 able to play Gateway, DOSMID and a slew of other things. Wahoo. I'm not changing the configuration or turning this off in hopes that I won't be able to get the HARDMPU to initialize properly again. That was a nightmare bugging me for a week.

I may swap out the 74LS with HCT as I have an abundance of those around the whole Xi8088 build. I don't think the 1284P is flaky, but I have some more on the way.

That board is pretty stellar. Is that the modern XT board?

bjwil1991 wrote on 2020-04-17, 04:15:

That board is pretty stellar. Is that the modern XT board?

Hello bjwil1991,

It is the modern XT Xi-8088 from Sergey's Projects.

The following have been assembled and working:

• MicroATX ISA Backplane
• Xi-8088 from above
• XT-CF-Lite V4
• ISA Floppy Disk and Serial Controller
• ISA OPL2 Card
• Lo-tech 8-bit IDE Adapter rev.3
• HardMPU

The following were sourced:

• Aztech Galaxy BX II
• Western Digital WD90C11-LR
• A revision of Oak OTI-077
• Western Digital WD1002A-WX1 when I feel like using the old Miniscribe MFM drives
• Some odd ball OPL2 card
• Danpex EN-2200T

The following still need to be assembled and have the parts to do so:

• Micro 8088 Board
• ISA Super VGA
• XT-IDE rev 4.1 as a kit

Last night I was successfully using the HardMPU with the Xi8088, WD90C11-LR or OTI-077, Floppy/Serial controller, XT-CF-Lite v4, Aztech Galaxy BX II. I noticed that once power up, I had to do a soft reset then the HardMPU starts working without a hitch.
I have some ICs I'm going to switch on the Xi-8088 board for some better versions that can handle 8+ MHz.

So far it has been a stable build. Also, there is the MT-32 with an unknown status to test. I hope it works, cause then it'll be even more awesome. SC-55 is okay and I can get by with that, but an MT-32 would rule.

-William

Tada! The MT-32 works! With the Micro 8088, HardMPU works on first cold boot unlike the Xi 8088 where I had to restart once for it to start working. Awesome!