SIMM banks in K2500

[ImaX]

Hi,

I'm trying to change the Sample-RAM in my K2500 rack, since the diagnosis reportet an error. But I don't understand how the RAM banks work:

In the diagnosis I first saw bank 0 and 1 were empty, while bank 2 and 3 had 32 MB each. When I opend the rack I saw two sockets and one SIMM-card inserted. So I think one socket holde tow banks, with two bank on one SIMM-card.

But now I put in another SIMM-card. On this card there were 8 chips on each side and 32Mb memory. When I inserted one of these chips in one socket the diagnosis reportet 8Mb on each bank, so all four bank were in use. When I inserted a second SIMM-card nothing changed, I think because all banks were already full.

But what is one bank? Does it depend on the SIMM-chip, how many banks it uses?

[Rexx]

My k2500xs has 8 simm sockets.
Yours has 2?
If so I would buy the 2x64mb simms to max it out to 128mb.

[ImaX]

I just wanted to change the broken SIMM-card - now I've got two of thos 32Mb cards and two socket, would make 64MB - and that's very enough for me.

Problem is that I can't use both cards, because one card already uses 4 banks, and that's what I don't understand..

I also read about 8 sockets in the manual for both the rack and the keyboard. I have opened my K2500XS once and took some photos, on these photos it seems as if there were 3 sockets.... very weird, but I don't want to screw it up again :-)

Perhaps... what is ONE socket? For me one socket is to put ONE 72pin-SIMM card in, is it? Or could you also put in two smaller cards and it's two sockets?

[Kurzweilfreak]

Your instrument has two sockets for 72-pin SIMMs. The third socket you're seeing, which is probably closest to you at the edge of the circuit board, is the socket where you would install the RMB-P2 piano daughterboard for adding additional ROM blocks. I would NOT put a RAM SIMM in that slot as there's no telling what might happen to it or your keyboard if you do.

I wouldn't worry about what the banks mean in the diagnostics mode; those are intended for service technician use and not end-user, and without a service manual, those numbers won't mean very much to you. All you need to know is that your instrument can accept up to two 72-pin SIMMs, with a max of 128MB total, using either a single 128MB SIMM, or two 64MB SIMMs. Make sure your SIMMs match in voltage as well.

Depending on the manufacturing age of your instrument, it could have either 2 slots for 72-pin SIMMs as yours appears to have, or 8 slots for 30-pin SIMMs as Rex's appears to have.

[ImaX]

Depending on the manufacturing age of your instrument, it could have either 2 slots for 72-pin SIMMs as yours appears to have, or 8 slots for 30-pin SIMMs as Rex's appears to have.

Aah, that's very good, now I know :-)) Thanks!

But my poroblem is also that the second 32Mb-card isn't accepted. I HAVE two 32Mb cards, but since one already uses all 4 banks (as shown in the diagnosis) the second one doesn't increase my memory (the diagnostics-screen doesn't change)...

[Kurzweilfreak]

You should be checking on the Master Mode page where it displays your amount of sample RAM available, and not worrying about what the diagnostic page shows. If the Master mode page doesn't show that you have somewhere around 65728 bytes (approximately 64 MB) then one of your SIMMs may be bad or seated incorrectly, or there may be a problem with the SIMMs socket of your board, although I'd find that to be unlikely.

Check the Sample display in the Master mode page first.

[ImaX]

I'll try that.. I have to remove it from the rack and screw it up again.. OH NO :roll: