About MSX 2 Sony HB-F9S upgrade to MSX2+ and...

By Dhampird

Hero (585)

Dhampird's picture

27-05-2010, 17:31

Hello everyone, i´m seeking info about how i could make upgrade to my HB-F9s to Mx2+ with chip Yamaha V9958 VDP and what kind of eprom/s is needed to put the basic 3.0 on it (i need what kind of eprom is it to try buy the chip online or in shop), i wonder if i could use a willen programer to program the basic 3.0 in that unknow eprom/s and how do it. I only find info about the soldering Yamaha V9958 VDP on a HB700, in this link:


Talking about join points 4-20-27 of the V9958 and then join 21-58 of the V9958, i´m wonder if this join points are the same for the upgrade on HB-F9S,
for the moment i dont have nothing info about the eprom kind to use and how to solder points if needed.

Another question is about upgrade 7Mhz (or more?) HB-F9S, i´m seeking about this also, but dont see nothing.

Please, anyone can help me with this?

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By RetroTechie

Paragon (1563)

RetroTechie's picture

27-05-2010, 18:06

A full 2+ conversion needs: 1. unsolder V9938 and solder in socket (=the hard part), 2. exchange with V9958 & re-wire some pins (easy), 3. add a 1-bit I/O port, 4. replace/add some EPROMs (likely a 27C256 + 27C512 combo, sure a Willem programmer handles those).

Without step 3+4, you don't have an MSX2+ but you can run software that detects a V9958 directly. You may be able to avoid step 3 with suitable ROM contents, but in that case you don't have the distinction between hardware/software reset that a 2+ makes.

So there's lots of ways to do it. IMHO: if you need to ask how, it may be more than you can handle (as in: bring to a successful end). An MSX2 -> MSX2+ conversion is not an 'old chip out, new chip in' kind of thing... Murdoch

The HB-F9S is a nice machine for this expansion I think. As for turbo projects: I designed the 'MSX Super Turbo' back in the days. I'm not sure if there's still a description online since it was mirrored on Hans Otten's site, who recently pulled most of the pages. If you need it: mail me. Running Naked in a Field of Flowers

By usuario_msx2

Paladin (745)

usuario_msx2's picture

27-05-2010, 22:41


I think I've answered you Wink

eprom with basic 3.0 is not neccessary unless you want to use VDP 9958 video modes from basic, you can run software that detects a V9958 directly.

as RetroTechie said, add F4 register is possible, maybe it helps you:
"Thinking in software", there is a few programs that uses it.

With z80 turbo mode, you can use Retrotechie design or it(I use it):

but with this machine I don't use a z80H, I use z80E


By Dhampird

Hero (585)

Dhampird's picture

28-05-2010, 05:12

Hello, thanks for replies, i´m think i´m are going very fast for now... first i will try steps 1. and 2. when i get the V9958 ,and check it if working well, then we can talk 3. 4. and turbo mode, i have to read more carefully about the process, is not easy at all. For the moment i have the info to begin to work.

Thanks for the replies.

By djh1697

Paragon (1427)

djh1697's picture

05-08-2015, 00:12

did you ever do this upgrade ?

By Alexey

Guardian (2639)

Alexey's picture

05-08-2015, 10:00

I can offer you a fully assembled F4 register board that you can mount on top of your Z80. Or you can get an F4/FMPAC combo board and you get a sound card and F4 board at the same time. Make your choice please. The combo board requires desoldering z80 and mounting it on top of the board. The board gets installed instead of z80, in a socket.

By djh1697

Paragon (1427)

djh1697's picture

05-08-2015, 16:35

I have not obtained it yet. Thank you, will let you know, I think finding a 9958 VDP is a good way to start though.