special 64 pin 1 or 4 MB 60 ns GVP SIMMs

[rkauer]

 There is a hack on Aminet to use regular 60ns SIMM on any GVP board.

 Works, but look like a total mess. Wires coming and going around.

 You can download it here:rtfm:

[rkauer]

hardlink wrote:
--ZIP--
...And thaks Rkauer for the hack tip - I like my hardware ugly  :-D

 @hardlink: you're welcome!:cheers:

 To everybody: yes, I notice the "friendly" prices of original GVP SIMMs, but back in the days, GVP made a choice:

 Permit the final user to use any crappy SIMM around and ruin the company name? Or make a special SIMM and sell it in the same market price?

 Result: GVP made is own SIMM, but the regular memory banks prices go down, GVP ones doesn't...

 Now everybody know what was happened after.

[rkauer]

 Check the first post I wrote about an aminet hack... :roll:

[rkauer]

countzero wrote:
if somebody has the eagle library for a 72 pin SIMM PCB, I believe we can derive a 64 pin GVP compatible from it.

Of course having the PCB produced will cost a lot (probably 50-100$ for the first prototype, 5$ ish for the boards after, add to that the trouble of unsoldering re-soldering ram chips from 72 pin SIMMs)

 If the problem is ressolder the chips, why not leave as-is?

 Simply make that aminet hack properly in PCB, with a SIMM socket to easy the job.

[rkauer]

countzero wrote:
I doubt it will fit in any accelerator with the SIMM socket.

 Probably you're right. So another approaching: make the hack in PCB, without the SIMM socket and solder (yes, solder!) the "equivalent" SIMM on the PCB in a parallel way (one "board" in contact with the other).

 That way we can avoid the mess of another socket (with the tilted board) and with only a "longer" SIMM. :idea:

[rkauer]

countzero wrote:
LOL I'm not sure this is easier than desoldering and resoldering RAM chips

anyway, primary problem is we don't have an eagle layout for 64 pin SIMM. Without that there's not much point in this discussion ...

 I think this is not a problem. GVP SIMM have the very same "step" as any 72 pin SIMM.

 And using the Aminet hack make the things a little bit easier.

 Sorry if I not help too much in the "GVP SIMM quest", I'm busy making another cool Amiga gear. The ppl who are in EAB know what I mean...;-)