Thanks. That link doesn't work for me though.
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64-Pin 4MB SIMMs for Apple Display Card 8*24 GC
- Thread starter jasa1063
- Start date
I assume not a Targa 1000 or Targa 2000 Pro? I am having trouble finding any Targa board with modules like that, other than an 8-bit ISA VMX which I assume has some sort of standard memory on it?
According to the RasterOps Horizon 24 manual, it technically supports up to 256MB of GWORLD memory. After toning out all of the lines on my own 1MB (4MB compatible PCB) SIMM, I came up with the attached pinout for the GWORLD SIMM. My SIMM has 8 256k x 8 DRAM chips on it in SOJ-26 packages. As some others have previously seen, it does appear that address line 9 is connected to the SIMM connector, meaning 4MB is possible. However, I also noticed that pin 59 on the SIMM wasn't connected to any of the memory chips or other lines. Pin 59 on all 4 SIMM sockets is, however, attached to pin 269 on the main RasterOps chip (RGS50228S41 on my card). I did find some internal docs on the Horizon 24, but after checking the pinout against my own chip, it does not appear that the development docs are accurate to the production chips (5v and GND are not in the right locations). If this mystery line is actually an additional address line (as it appears to be), it should be possible to put 16MB SIMMs in the Horizon 24, giving it 64MB of total GWORLD/RAM disk memory.
Depending on how much free time I end up with this winter, I may try putting a PCB together to test my theory; but I at least wanted to share the work I had done so far.
Depending on how much free time I end up with this winter, I may try putting a PCB together to test my theory; but I at least wanted to share the work I had done so far.
I think this guy sells them
PurpleRAM GWORLD 2MB (1MB x 2) 64-pin SIMM kit by Jurassic Computing on Tindie
PurpleRAM GWORLD 2MB (1MB x 2) 64-pin SIMM kit for Apple, SuperMac and RasterOps NuBus graphic cards
www.tindie.com
EDIT: Just noticed Out of Stock note. Maybe something to keep an eye on.
As far as I can tell, the 8*24 GC and SuperMac Thunder/24 will both only accept up to 4MB SIMMs. The SuperMac card will also only accept 2 4MB SIMMS, not 4. The RasterOps Horizon 24 (and possibly the PaintBoard Professional, but I haven't seen any definitive docs or card photos to prove it) is the only card that supports more than 8MB of GWORLD. The GWORLD SIMMs don't seem to have any presence detect functionality on them, so it would be up to address line probing or jumpers on the card to configure it (maybe that is what the mystery jumper on the Horizon 24 does?).
Siliconinsider makes some great stuff, so if you are looking for just 1MB GWORLD SIMMs, I would definitely recommend their store. It does look like they are currently out of stock, but I have run into that before when buying from them and everything I have waitlisted so far has come back up eventually. I don't plan on doing any batch runs of new SIMMs (I don't want to track down old DRAMs or de-solder a bunch from my big box of memory), but I'll definitely have leftover blank PCBs that I'd send out for free if I get them working. I'll also open source the schematics/board/gerber files so someone else can make more if desired.
Siliconinsider makes some great stuff, so if you are looking for just 1MB GWORLD SIMMs, I would definitely recommend their store. It does look like they are currently out of stock, but I have run into that before when buying from them and everything I have waitlisted so far has come back up eventually. I don't plan on doing any batch runs of new SIMMs (I don't want to track down old DRAMs or de-solder a bunch from my big box of memory), but I'll definitely have leftover blank PCBs that I'd send out for free if I get them working. I'll also open source the schematics/board/gerber files so someone else can make more if desired.
Hey everyone, sorry for letting things up in the air for a while.
I actually now have a working 4MB design, my original PCB had an issue with A9 which was not impacting the 1MB SIMM.
My supplier ran out of 1Mx4 RAM chips. I have been looking for options but I hope I can have a batch made by early next year.
I actually now have a working 4MB design, my original PCB had an issue with A9 which was not impacting the 1MB SIMM.
My supplier ran out of 1Mx4 RAM chips. I have been looking for options but I hope I can have a batch made by early next year.
Checking back in to see if you were able to make some @Siliconinsider ?
Didn't realize this thread was still active. I'd love to populate my Thunder 24.
Yes I have, I need to list them... You can DM me here as it will be faster. I have about 20 at the moment.
Thanks for checking in.
@Siliconinsider they seem to work great! Thanks so much! I inserted two 4MB modules in my Thunder/24. They seem to need to be staggered (slots 1 and 3).
What would be the best way to test the functionality of these? I believe Finder uses GWorld? So if it is working that's a good sign?
What would be the best way to test the functionality of these? I believe Finder uses GWorld? So if it is working that's a good sign?
But firstly you have to put a GWorld plug-in into Plug-ins folder
GWorld was a mess at the time.
How large would be appropriate in resolution? I'll try a 24-bit image.
I have placed 16MB in my SuperMac Thunder/24 and can confirm that only 8MB are seen, so 8MB seems to be the maximum amount of GWORLD RAM supported.
I have a RasterOps as well, I need to find the drivers and test it, there's some damaged pins on a QFP so it may need a little bit of repair before I can try it out.
I have a RasterOps as well, I need to find the drivers and test it, there's some damaged pins on a QFP so it may need a little bit of repair before I can try it out.
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