Jo22 wrote:

How about the Zilog 80 ? It's old, had been copied a thousand times and it's an eternal classic. 😀

It’s not MCU - will require at least external ROM/RAM. Also can find a number of other reasons not to use it. Most important one for me - I don’t like Z80 😀

Zilog does have MCU versions of the Z80, but I'm not clear on how usable they are with free tools. I do know that the z8 micros require the proprietary compiler.

Unfortunately, killed my card while connecting the optocoupler interface, wasn’t careful enough 🙁
Will take some time to update the card with MIDI interface and make new one.

Oh, well. My condolences.. 🙁
I hope you can fix it somehow..

Which kind of optocouplers do you use, if I may ask ?
I like the old MB10x series, for example.

Since you're looking for a new MCU (µC), what about the ATMegas from Atmel/Microchip ?
As far as I know, they share the same opcodes and have enough oomph to emulate a Z80 home computer..

Jo22 wrote:

Oh, well. My condolences.. 🙁
I hope you can fix it somehow..

It's a good opportunity to make upgraded card with MIDI and CODEC. Just annoying to be delayed with the firmware development...

Jo22 wrote:

Which kind of optocouplers do you use, if I may ask ?

Already had 6N136

Jo22 wrote:

Since you're looking for a new MCU (µC), what about the ATMegas from Atmel/Microchip ?

I know ATMegas are very popular (especially because of different Xduinos), but I always wanted to play with STM32, so will use them, if time comes. For now it's just NIOS II "soft" CPU within FPGA - extremely flexible for a development/debugging purposes.

most atmega is easier for isa card since they are 5v. does stm32 come in 5v version or only 3.3 + 1.8? I know a lot of PIC migrated down to 3.3 + 1.8 so its a pain to get 5v versions for stuff now. ugh

Philips makes 5V compatible ARM parts, but you need a CPLD or FPGA anyway and those will be 3.3V so there's no point going with any 5V parts, just use 3.3V parts exclusively behind level translators. Much more parts to choose from and much better cost on them too.

newold86 wrote:

Unfortunately, killed my card while connecting the optocoupler interface, wasn’t careful enough 🙁
Will take some time to update the card with MIDI interface and make new one.

When you say MIDI interface, are you speaking about a wavetable header? Because I would love that on an 8bit sound card.

Tiido wrote:

you need a CPLD or FPGA anyway and those will be 3.3V so there's no point going with any 5V parts, just use 3.3V parts exclusively behind level translators. Much more parts to choose from and much better cost on them too.

Exactly, it's what I'm planning to do

jarreboum wrote:

When you say MIDI interface, are you speaking about a wavetable header? Because I would love that on an 8bit sound card.

I was trying to connect MT-32...

Wave Blaster header is extremely simple, it will be a part of the new card's design

If a combination of FPGA and uC is on the table, I'd like to put forward the Zynq family again. Just the ability to reduce parts count is very attractive.

gdjacobs wrote:

If a combination of FPGA and uC is on the table, I'd like to put forward the Zynq family again. Just the ability to reduce parts count is very attractive.

First of all, I have exactly ZERO experience with Xilinx, so not looking into Zynq at all...
Also, it's very possible that using FPGA+hard CPU on one chip will INCREASE a parts count - separate MCU will have enough Flash/RAM inside, while SoC could require additional external memory...

P.S. But I have looked at this possibility for a different project (basically, reasonably powerful single board computer in ISA8 form factor, that can run Linux or similar and interface with ISA bus).

Are you an Altera man? I believe Intel has a similar solution out.

Intel has such parts too, but like Xilinx they're not exactly cheap and none come in QFP or other packages that aren't BGA, keeping stuff firmly out of DIY levels. Also using the ARM CPU just for SB and MPU is a huge waste, and to do more you need DDR external memory which pushes it even more out of DIYable thing. Softcore makes lot more sense.

What's the incremental cost in gate count for a NIOS?

Least logic resources requiring NIOS config fits in under 1k LEs, so you can use the lowest cost FPGAs that Altera/Intel offer which have 2k LEs while still having decent amount of IO in QFP packages (10...20€ range parts).

Official number for the smallest NIOS II - around 750 LEs. Kind of "Hello world" NIOS II project takes around 1300 LEs (on MAX10).
4K MAX10 in QFP package is around $15. But it has only a bit more than 16K of memory - could be not enough...

To me, it sounds like coupling the FPGA with an STM32, PIC32, or the like would give you more breathing space for not much additional cost. If you can port across (SB Pro/SB16/OPL3/GUS/Adlib Gold) functionality from, for example, DOSBox, you might end up saving quite a lot of time and effort. The FPGA would be excellent acting as bus logic glue and could probably be used to implement soft reconfigurability for I/O resources.

Have some time issues, so not too much to report...
Anyway, managed to finish new test card design and started the PCB tracing (hate this part !).

Does anyone know a good SB test program, that can test DSP part accordingly to specific DSP version ? While the new card's PCB is being traced by someone else, I already fixed my old card and re-wrote the software - at the moment looks like I have working all sound output related DSP commands from "Sound Blaster Series Hardware Programming Guide" (up to and including DSP v4.xx).

It works quite well with games I have tried with, but would like to test it more extensively (switching DSP versions)...

Also, I know there are many more commands, than described in the above-mentioned manual, how widely are they used ?

newold86 wrote:

Does anyone know a good SB test program, that can test DSP part accordingly to specific DSP version ?

Not really, but NSSI and Dr. Hardware do a bit of DSP detection.. That's all I know, sorry. 🙁