Guillian, thanks a lot!

I was hoping that someone with skills and experience will pop-up

I want to make this upgrade in two steps:
1) upgrade to 256Kb and see if all works fine
2) upgrade to 512Kb by adding two more 44256-es...

For the first step (i.e. 256 kb), is it enough to do just this:

- Remove IC22 and IC23 chips and capacitors (you can use that chips to upgrade your VRAM to 192K)
- Put that capacitors and 44256 chips in IC21 and IC24

It is a good idea to do it in two steps. But for 256K you will also need to:
- remove (J2) resistor
- solder a wire on (J3) to short it.

Thanks, that sounds clear enough

Manuel,

Thanks again for instructions. Unfortunately I have hard time locating 44256 chips... My local IC dealer only has 41256, which is no good... Can you sell me 4 x 44256 chips?

If you'll sell me 44256 chips I will order the Flash SCC cartridge as well. Flash SCC cartridge is 60 euro if I send you Konami SCC game. Do you need the whole game including casing or just the pc board with SCC chip? I am asking because I can use plastic case for my Padial 4MB mapper.

I already know what I will to with 2 x 2464 chips. I have a Yamaha CX5M computer, it's alnost MSX2. I'll increase VRAM from 64 to 128KB.

Will Panasonic A1 WSX work without internal RAM and external 4MB Padial mapper? I'm curious, since I can't locate 44256 chips fast, but I would like to upgrade VRAM in CX5M already...

Thanks,

Adrian

Quote:

Will Panasonic A1 WSX work without internal RAM and external 4MB Padial mapper?

It will not work without internal RAM, but it will happily work with both. It's part of the MSX standard
If you insert a 4MB Padial Mapper, your bootlogo screen will say "4160kB Main RAM" and you'll be on your way to playing many cracked konami games

Quote:

If you insert a 4MB Padial Mapper, your bootlogo screen will say "4160kB Main RAM" and you'll be on your way to playing many cracked konami games

What would Maico Arts' MSX Turbo R GT say then, when booting? He said he had 13,5 Megs (!!!!) of RAM in his MSX. That is, 3 external 4M, 1 external 1M and 512 by the GT's default... But who's gonna use such a huge stack of memory anyway? I don't think he's got it all plugged in all the time tho. Would be quite stupid if he did. Not enough slots left for SCC and MegaSCSI and that sorts of stuff

Quote:

Thanks again for instructions. Unfortunately I have hard time locating 44256 chips... My local IC dealer only has 41256, which is no good... Can you sell me 4 x 44256 chips?

I don't have such chips. I just found them in an old PC. I'll ask in some local stores for you.

Quote:

If you'll sell me 44256 chips I will order the Flash SCC cartridge as well. Flash SCC cartridge is 60 euro if I send you Konami SCC game. Do you need the whole game including casing or just the pc board with SCC chip?

It is enough with the SCC cartridge board. But then you will lose the nice cartridge label

Hmm, so you do reuse Konami cartridge cases...

How do you open them without damaging internal micro-hooks (I hope you understand what I mean)?

And another thing: can you expand my SCC+ from Snatcher with more RAM, so I can run games from it? For a price of course

Thanks!

Manuel, earlier you mentioned what the 2 x 32 KBytes dram chips can be used to extend VRAM to 192 KB.

Will MSX bios actually report 192 KB in logo boot screen?
Is where any apps that know how to take advantage of extra VRAM?
Does more VRAM means more pages for flipping?
Hmm.. do you know if it's very hard to do the ADDRAM thingie (direct access to VRAM from Z80)?

What is the absolute maximum VRAM can be expanded to? 256KB? 512KB? More?

Quote:

How do you open them without damaging internal micro-hooks (I hope you understand what I mean)?

It is easier doing it that explainig it (^^!)

There are 6 micro-hooks and notchs:
- 2 under the label
- 2 in left/right sides
- 2 in the upper side

Just force the hooks a bit to release them from the notchs. Try first the ones under the label (you can see them easily). I use a plain and small screw-driver. After releasing that hooks, you can open just a bit the case (the cartridge conector part).
Then force both sides, just in the middle (use the screw-driver as a crowbar)
Now you should open the case easily.

Quote:

And another thing: can you expand my SCC+ from Snatcher with more RAM, so I can run games from it? For a price of course

Yes, it is quite easy to do it. You only need to add two 464 chips to the board. You can use the ones removed from A1-WSX

Quote:

Will MSX bios actually report 192 KB in logo boot screen?

As far as I know, it will not be reported. It wasn't reported in my turbo R.

Quote:

Is where any apps that know how to take advantage of extra VRAM?

FastCopy uses it. Don't know if there are more aplications/demos/games that take adventage of it.

Quote:

Does more VRAM means more pages for flipping?

You will have 64K extra memory for storing data in the VRAM (gfx or whatever you want). But if my memory serves me well you can use it for flipping, since you need to read/write data to the expasion using VDP commands (i.e.: COPY).

Quote:

Hmm.. do you know if it's very hard to do the ADDRAM thingie (direct access to VRAM from Z80)?

I don't know. I have never seen ADDRAM and I'm not a hardware expert (^^!)

Quote:

What is the absolute maximum VRAM can be expanded to? 256KB? 512KB? More?

I think the limit is 192K

Quote:

I don't know. I have never seen ADDRAM and I'm not a hardware expert (^^!)

Yeah right So far you have been the most experienced person willing to help other MSXers! It is possible that SunRise and Bas know more then you, but they are not reading posts here or do not have time to help MSX enthusiasts...

Quote:

And another thing: can you expand my SCC+ from Snatcher with more RAM, so I can run games from it? For a price of course

Dude!! Please!! don't violate a Snatcher cart. That would be such a pity

Hi Manuel!

What I did so far:

- bought ISA ATI SVGA card with four 44C256 ICs:
tht.net/~aoboroc/msx/isavga1.jpg
tht.net/~aoboroc/msx/isavga2.jpg

- desoldered IC22, IC23, C89 and C90;

- soldered capacitors back into C88 and C91;

- soldered sockets for DIP-20 chips in IC21 and IC24 and inserted two 44C256 chips:
before: tht.net/~aoboroc/msx/a1wsx06.jpg
after: tht.net/~aoboroc/msx/ic21-24.jpg

Now I should do this:

Quote:

(In the other side of the mainboard) - Search for the MSX engine T9769. - Next to it you can find printed on board (J3) and (J2) - Remove the resistor in (J2) - Solder a sort wire in (J3), so you get +5V in pin 52(T9769)

but I have trouble locating J2 and J3. I only see J1 and J4



Please tell me what is aproximative location of J2 and J3 (like C4 or D2...)

You worked on WX, is it possible WSX doesn't have J2 and J3 at all?

Thanks a lot!

Manuel, your help with SCC+ was awesome! Everything worked great:
dhau.blogspot.com/2004/05/i-upgraded-msx-snatcher-scc-cartridge.html