My 1200 RAM

[Eclipse]

Hi just a quick one,
I noticed that most RAM expansions have the PLCC sockets empty especially if no FPU is added.
Although mine has the FPU it was added sometime after the card was bought.
If you look at this picture you will see it has the AMD MACH130 which I'm almost certain would not be needed for a simple RAM board as the 130 is a CPLD.
If you look at the expansion it looks as though there was a SCSI version.
Anyway, is it needed. Anyone have any pictures of the SCSI version



EDIT: I know the battery is missing, I've just taken it out.

[Eclipse]

Well what have we here
I could fit those IC's and caps no problem. Getting that ROM though is a different matter. I'd have to copy it from a working board.

[Jope]

You need the GAL's contents too before you can have SCSI.

[Eclipse]

Yep,
They can be a bit of a pain to read, especially if the security fuse is blown.

[Zetr0]

@Eclipse

that indeed would be an interesting project to review... but as you say getting the firmware might / will prove difficult...

[Eclipse]

Just some mild Pr0n for Lord Zetro.
Cut the track from the battery positive and fitted an 1N4148 in series with the circuit so it doesn't charge. When powered I see only 3V accross the battery so it's resisting the charge.
The battery is now the commonly found CR2032.
I'm surprised some sort of sticky or guide hasn't been made regarding batteries in Amiga hardware though.

That 68882 is really quite pointless in there isn't it? I really don't use anything that uses the FPU and the card works fine without it. I've seen them sell well on ebay. Worth selling it anyone reckon?

[Zetr0]

@Eclipse

!AWESOME!

MMmmmMmmmm some nice pr0n there

a great job on the battery too I totally agree there should be a sticky, as you suggest its quite a common fault!

jopealicious is the guy that can make this happen

one thing i have noticed in the picture, in the first one

top of the board, the top IC second from right (74F257N) looks damaged... or atleast brutalized... I have also noticed this in the reference picture too...


very strange me thinks.

thinking about the SCSI, i wonder if there was only firmware type ? rather than writing two CPLD's its possible that only one would of been made....

hmmm yes i can understand the point of the FPU, especially as its linked to the mobo speed of 14mhz. you could add an OSC, but.... again... what would be the point with only 4mb ram ?

I have seen PGA FPU's sell between £5 and £45 depending on frequency and condition.

[Eclipse]

Pics resized now,
The 74F in the top right has some sort of factory mod/hack/hash job on it.
They've lifted the legs and soldered some enamelled wire in place. I've never liked using enamelled wire to do mods as it can easily scratch the coating off and you are left with bare wire.
I'm still investigating the SCSI I will keep you informed. I agree a generic CPLD program is quite possible.

Regarding the mod.
Many people have done it on many different boards so should be "fairly" easy to make a guide.

[fc.studio]

You have an XC68882RC50A FPU. In the past I read MC FPU version is better than XC 'cause the first should support a bit the overclocking. However, although your version is XC, you have the top 50 MHz speed and I don't know boards (RAM, 68020 or 68030) requiring higher speed. This is perfect for a Blizzard 1230 IV, but it surely works on any other boards supporting PGA FPU.
At the moment, on selling it on e-bay, you can probably get at least € 30.

[alphonsus]

IIRC, the only 68k FPU released officially faster than 50MHz was the one in the end-of-days 66MHz 060's. People have overclocked further, though.