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Old 27 February 2017, 17:48   #11
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Thanks everybody. I'm glad this work is helping.

@demolition - Yep, I did see tbtorro's work while I was initialing researching. Alas, the A530 only uses 1M and 4M SIMMs so I had to roll my own.

@dalek - I've only run into a few board houses that required a separate board outline during my career so I don't think much about it much. Thanks for bringing this issue to our attention. I cooked up a new batch of gerber files that now have a separate board outline file and attached them in the ZIP file with the name "GVP Compatible 4MB 64-Pin SIMM Rev A - Sep" for "Separate Outline". Protel 99SE uses mechanical layers for board outlines so in the ZIP you'll see a new gerber file with the file extension .GM4 for gerber mechanical layer 4 (which is where the outline is in the project). You can rename the file extension to whatever your board house needs to identify it as a board outline layer.

Speaking of 1M SIMMs. If anybody is interested this is the same board you would use for a 1M SIMM module. The 256K by 4Mbit chips used on the 1M SIMM module and the 1M by 4Mbit chips used on the 4M SIMM module both come in the same 20/26 SOJ package. The only difference between them is that pin 5 (address 9) is not used on the 256K by 4Mbit chip. I traced out the GVP 1M SIMM module I have here and A9 is indeed routed to pin 5 of each chip on the board. Since the pin is not internally connected no harm done. GVP Could use the same board for both module sizes. The chip package for the DRAMs on the 16M SIMM is a 24/26 SOJ, as shown in grelbfarlk's pictures above, so a separate board is needed for them.
Attached Files
File Type: zip GVP Compatible 4MB 64-Pin SIMM Rev A - Sep (98.3 KB, 159 views)
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