F4/FMPAC Light Combo Board project

Guardian (3648)

26-05-2016, 22:58

Pablibiris wrote:

Nice!,thanks again
I hope I'm not too affected by the lack of those extra blocking capacitors and extra noise suppressing capacitor in the new version

No, version 1.2 is quite good when it comes to noise suppression. Just connect the audio wire to SND pin if SPK pin's output is too noisy for you.

By Wierzbowsky

Guardian (3648)

30-05-2016, 00:25

The project files can be found in our Github repository:

https://github.com/RBSC/F4-FMPAC

By storhemulen

Supporter (8)

01-06-2016, 12:25

Just to make sure, the silk screen error with 74LS74 and 74LS125 swapped is corrected in version 1.3?

By Wierzbowsky

Guardian (3648)

01-06-2016, 14:09

storhemulen wrote:

Just to make sure, the silk screen error with 74LS74 and 74LS125 swapped is corrected in version 1.3?

Yes. Corrected in version 1.3.

By Pablibiris

Paragon (1834)

08-06-2016, 22:00

Hi Alexey!
There is some problem if I use R3 as 169K resistor instead 170K? (I'm not sure the version of this board ^^)

http://www.msx.pics/image/Rjjo

By Wierzbowsky

Guardian (3648)

08-06-2016, 22:34

Pablibiris wrote:

Hi Alexey!
There is some problem if I use R3 as 169K resistor instead 170K? (I'm not sure the version of this board ^^)
http://www.msx.pics/image/Rjjo

This is v1.2 board. The 169k resistor should be fine.

By Wild_Penguin

Hero (644)

12-07-2016, 14:15

Hi Alexey,

Pardon me if this information is already somewhere, but is there a list of ROMs (what sha1sums) that are to be used if one want's to install a ROM (or if they are legally downloadable, post the link here)? Or does it actually matter, as long as it is from any working fmpac clone? The Original FMPAC ROM is 64kb, I presume some clones - without the built-in demo/SRAM manager - have a 32kb ROM. Which are the 16kb ones (for the 27c128)? Are any PLCC32 flash chips compatible with EPROM?

I will most probably be installing a 27c512 here at some later point, though, just asking to know the alternatives. That being said, does anyone have spare YM2413 in Finland? (maybe I should post in the sales section...).

Also - I presume I could put anything into the ROM, say, a DOS2 ROM (in case something else than fmpac is desired)?

By Wierzbowsky

Guardian (3648)

12-07-2016, 14:33

Wild_Penguin wrote:

Hi Alexey,
Pardon me if this information is already somewhere, but is there a list of ROMs (what sha1sums) that are to be used if one want's to install a ROM (or if they are legally downloadable, post the link here)? Or does it actually matter, as long as it is from any working fmpac clone? The Original FMPAC ROM is 64kb, I presume some clones - without the built-in demo/SRAM manager - have a 32kb ROM. Which are the 16kb ones (for the 27c128)? Are any PLCC32 flash chips compatible with EPROM?
I will most probably be installing a 27c512 here at some later point, though, just asking to know the alternatives. That being said, does anyone have spare YM2413 in Finland? (maybe I should post in the sales section...).
Also - I presume I could put anything into the ROM, say, a DOS2 ROM (in case something else than fmpac is desired)?

The ROM images for this board are available in our repository:

https://github.com/RBSC/F4-FMPAC/tree/master/ROM

If you use 27c128 chip, just put the "internal.rom" image in it. If using the 27c256 chip, put the "combined.rom" image in it. For 27c512 you can put the "combined.rom" image there twice (add one image to another to get 64kb). With 27c256 and bigger chips you will be able to select the internal/external ROM with a jumper if you have board version 1.3.

I tried to make the full FMPAC bios work with this board, but didn't finish that project because all my chips were OTP and I wasted 3 of them by trying to make the full image work. If you put the full bios image in the slot it just doesn't work properly though it should.

It's probably possible to put the full or partial bios image somewhere in the main subROM, but our experiments with Yamaha computers were not a success. The bios was not found by older applications, so we kept the bios on the board.

By Wild_Penguin

Hero (644)

13-07-2016, 12:13

Hi Alexey, thanks for your answer. I've been to that github repo but somehow missed that folder

Just one more question: why specifically 27C series, and EPROM? I mean, there are more readily available, and more modern pin compatible ROM chips available. Is there some reason to not use 29c256 or 28c series EEPROM, or for example GLS27SF512 ? I'm asking because I really don't know much about ROM chips =)

By Wierzbowsky

Guardian (3648)

13-07-2016, 14:46

Wild_Penguin wrote:

Hi Alexey, thanks for your answer. I've been to that github repo but somehow missed that folder
Just one more question: why specifically 27C series, and EPROM? I mean, there are more readily available, and more modern pin compatible ROM chips available. Is there some reason to not use 29c256 or 28c series EEPROM, or for example GLS27SF512 ? I'm asking because I really don't know much about ROM chips =)

AFAIK the 29c and other EPROM series are not pinout identical with the 27c series. We used the 27c series because the original design of the FMPAC lite module was based on that EPROM series, we just used the PLCC32 version to save space on the board. You can buy the 27c512 EPROMs in China quite cheap. In EU they are 2.5 euro each. Still bearable.