F4/FMPAC Light Combo Board project

Page 4/15
1 | 2 | 3 | | 5 | 6 | 7 | 8 | 9

By Alexey

Guardian (1985)

Alexey's picture

12-08-2015, 09:15

NYYRIKKI wrote:
Alexey wrote:

I will be ordering the FMPAC/F4 combo boards soon. At least 6 will be available for sale. Timo, how many do you need?

It all depends of the details... Is it possible to get it with parts? assembled? with ROM burned? What is the price?
Yet again... I'm fine with DIP sized components, but smaller than that... It is total lottery do I get a working device or do I end up dismounting the traces from the board while desperately trying to fix my errors.

I can solder all smd components for you and program the rom chip. You will need to solder only 3 chips in dip cases and desolder your z80 to install the socket on the motherboard. A half assembled board will cost 25 euros, but you will need to buy z80, 2413 and 4558 yourself as I don't have those chips for sale.

Also if I can't find a reasonably priced 27c128 rom chip, I will use 27c256, program the fmpac rom twice into it and connect the chip to cs0 so that the roms are visible in both 0000h and 4000h.

By NYYRIKKI

Enlighted (5199)

NYYRIKKI's picture

12-08-2015, 10:42

Alexey wrote:

I can solder all smd components for you and program the rom chip. You will need to solder only 3 chips in dip cases and desolder your z80 to install the socket on the motherboard. A half assembled board will cost 25 euros, but you will need to buy z80, 2413 and 4558 yourself as I don't have those chips for sale.

That sounds perfect! I'll take two. If you want to sell more of them, I'll also ask from Ahti/STT. I started to wonder if the board is small enough to fit on place of Z80 on my SVI-738... but if it's not, I think I can just install short jump wires between Z80 legs and holes on the board. This way I don't even need to desolder the Z80.

Quote:

Also if I can't find a reasonably priced 27c128 rom chip, I will use 27c256, program the fmpac rom twice into it and connect the chip to cs0 so that the roms are visible in both 0000h and 4000h.

Almost right.. but you need to use /CS01 = A15. Other than that this sounds good. FMPAC.ROM will be read always from upper side of the chip, no matter if A14 is connected to +5V or A14... If it is connected to A14 and you leave lower side empty, then the ROM will be visible only one time and on correct location.

By maxis

Champion (512)

maxis's picture

12-08-2015, 10:51

Grauw wrote:

For the Yamaha CX5MII, as you can see in its service manual, all slots are already occupied.

For CX5MII it is the case, but not for YIS503/III, where the side slot connector is not mounted.

So Alexey, you can try out using slot select 3.1 (front FW microslot) as a temporary solution to check out your board if you have access to YIS503/III (I'm sure that you have ;) ).

By madscient

Master (177)

madscient's picture

12-08-2015, 21:31

Most of MSX2 using S1985 is not expand SLOT0.
If you want to place FMBIOS on SLT0x, you should configure S1985 as to expand SLOT0 first.
Typically, it means connecting a diode between /RST and /X3 of S1985.

If SLT02/CS0 and SLT03/CS01 of S1985 used as /CS0 and /CS01 in your machine, you can use only /SLT01.

By OeiOeiVogeltje

Paragon (1232)

OeiOeiVogeltje's picture

12-08-2015, 22:33

am i to understand that with this board its possible to have an F4 and a working FMPAC in
for example a philips 8245?
if yes i want 2!

By NYYRIKKI

Enlighted (5199)

NYYRIKKI's picture

13-08-2015, 09:36

Just to avoid any possible confusion... This is not FM-PAC (because there is no PAC implemented) but an MSX-MUSIC + F4 I/O implementation that you can mount between Z80 and your MSX... Perfect for MSX2+ upgrade and great even for normal MSX2!

By madscient

Master (177)

madscient's picture

13-08-2015, 21:53

If you want perfect upgrading, you might need further roms mandatory for MSX2+.
It means, MAIN bios, SUB bios, Kanji font and Kanji driver rom.
The Kanji driver rom contains boot logo.

By OeiOeiVogeltje

Paragon (1232)

OeiOeiVogeltje's picture

13-08-2015, 22:21

i already have that
my 8245 has all except the F4 and FM thingy (i dont need the kanji stuff)

so

where/how can i order?

By NYYRIKKI

Enlighted (5199)

NYYRIKKI's picture

14-08-2015, 10:47

madscient wrote:

Kanji font and Kanji driver rom.
The Kanji driver rom contains boot logo.

As the Kanji is mostly interesting for Japanese users, leaving these out is not a big problem... On my MSX2+ mod I left out the Kanji stuff... As I still wanted boot logo, I needed to get rid of "M", "S" and the nice animation in order to cram it back to SUB bios where it was moved from when MSX2+ BIOS was originally made. Other dirty details in description of this video.

By madscient

Master (177)

madscient's picture

14-08-2015, 13:25

NYYRIKKI wrote:

As the Kanji is mostly interesting for Japanese users, leaving these out is not a big problem...

Yes, you are right. Personally, I think Kanji and F4 feature are not so necessary for MSX2+.
(F4 register was added to solve Kanji rom problem on warm booting, mainly.)

In the boot sequence of MSX2+, sub rom calls $7A00 of its own slot for boot logo.
(It means, sub rom and kanji driver must be placed on the same slot)
Logo program and data is mapped on $7A00-$7FFF of kanji driver.

Fortunately, MSX-MUSIC bios is very hollow and enough to implement boot logo.
Then, you can override $7A00-$7FFF of MSX-MUSIC bios with boot logo, and place it on sub rom slot.

I have upgraded some MSX2 which has no kanji features with above method.

Page 4/15
1 | 2 | 3 | | 5 | 6 | 7 | 8 | 9
My MSX profile