128megs on a CSA Derringer 030

[Oldsmobile_Mike]

1.) I'd need the A2000, the Accelerator, and the RAM.
2.) It would be much more productive to just go ahead and wire in 72pin SIMM sockets. Less connections, less of an unorthodox "ass-rig" and if the dram ever went bad, you'd be able to replace the SIMMs.
3.) You are talking about a VERY involved project. Not something worth writing up for others to easily attempt.
4.) Yes, any machine with at least a 68020 has a 32bit data bus and at least 4 gigs of physical address space. Its just a matter of designing the dram control/address circuits (or modding existing ones) to get the dram on the bus.
5.) I'd be willing to look at anything, and even attempt anything if price is no object, but unless theres already a standard simm socket there, the end result is not gonna be an easily repeatable "hack".

Ah, makes sense.  I don't know if anyone has ever managed to replace GVP SIMM sockets with standard ones?  You've given me something new to look into, thanks!  

[JanciB]

Avail shows largest block 16MB. I think that's normal.

Sysinfo shows largest block 65MB. I tested it. Created 28MB lha archive in ram:. Without errors. Tested the archive. Without errors. Nice.

J.

[joekster]

I did some software work for CSA on the MMR. I had a version that supported 2MB of SRAM. I suspect that it was a simple hack like the dram...

512k x8 srams are the same 32-pin dip as the regular 128k x8. should just be a matter of wiring in two extra address lines.

[mechy]

Ah, makes sense.  I don't know if anyone has ever managed to replace GVP SIMM sockets with standard ones?  You've given me something new to look into, thanks!  

they have

http://aminet.net/package/docs/hard/gvpsim64
gvp simms are wired quite different than typical 72 pin simms but its possible to adapt it.

[Oldsmobile_Mike]

they have

http://aminet.net/package/docs/hard/gvpsim64
gvp simms are wired quite different than typical 72 pin simms but its possible to adapt it.

I found that this morning, actually.  Too bad most of the instructions/pictures are in French.  Ah, FML!  :laughing:

[JanciB]

I got my 128meg SIMM from Mech of a4000t.com

What is he type of the chips on your 128MB SIMM? Could you make a photo?

Thanx

J.

[Metalguy66]

This is the 128meg SIMM I use:
http://www.amiga.org/forums/attachment.php?attachmentid=4015&stc=1&d=1424019471

[JanciB]

Hmm, your memory chips are for 3.3V like mine too. Do you think
they can manage 5V too? I did not have problems with mine yet, but there
is duscussion on other forums that 5V can destroy them.

J.

[Metalguy66]

Yeah, you are right. I never even thought about the possibility of 3.3v SIMMs vs 5v SIMMs.

The GM71V65403CT5 is a 16meg x 4bit dram with 3.3v supply +/- 10% tolerance.

I am measuring 4.5VDC between VCC and VSS pins on the chips, when the SIMM is installed on the Derringer.

That's not good..

If I am unable to find a similar SIMM with 5v rated chips, I may order some small SMT 3.3v regulators and install them inline with the VCC rails on the SIMM, itself.

[kolla]

4.) Yes, any machine with at least a 68020 has a 32bit data bus and at least 4 gigs of physical address space.

Carefull, it is not "at least 4 gigs", it is a theoretical maximum of 4 gibibytes of physical address space, and in reality less (some address is reserved to chipram for example). Oldsmobile here is very sensitive when it comes to this kind of information.

[Oldsmobile_Mike]

Carefull, it is not "at least 4 gigs", it is a theoretical maximum of 4 gibibytes of physical address space, and in reality less (some address is reserved to chipram for example). Oldsmobile here is very sensitive when it comes to this kind of information.

Still trolling?  Glad to know I hit a nerve.  :roflmao:

FWIW, @Metalguy66 did say "at least a 68020", not the 16-bit data bus / 24-bit address bus 68000, which was the basis for your whole idiotic argument in the first place.  

Edit: PS - what is a "gibibyte"?  :p  Also, chip ram reservations are because of the Amiga architecture, not a limitation placed by the processor itself.  Man, I can't think of a single accurate statement in your entire post.  Bye!