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Old 02 February 2018, 10:34   #68
solidcore
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Join Date: Sep 2017
Location: birmingham, uk
Posts: 548
Myself and Kipper2k spent a day or so figuring this out the other month, so correct if wrong but I came to the following conclusion:

As the a1200 is a 24bit, even a PMCIA card being present (ram, ethernet or ide will conflict) on the active line? causes the amiga to automatically reserve the memory therefore conflicts with the 8mb Fastram configured address space (4mb of the 8mb Zorro-II memory address window), this will cause a crash I believe with any PMCIA inserted into the slot except with certain kickstart rom and workbench configurations which we found one particularly worked I think it was kickstart 3.0 with workbench 3.1 and not kickstart 3.1.

A hardware jumper to switch between 4mb and 8mb configurations on a k1208 would allow PMCIA cards to work harmoniously in 4mb mode at the cost of 4mb fastram.

Regardless of workbench or kickstart rom you use to get it working, ram sharing the same space will end horribly. There is really no point in PMCIA ram and z2 8mb fastram together.

However sunshine over the hills for the k1208 would be to reimagine a k1238 - an 030 card for the a1200 with even more memory (not sure how much) possibly with a FPGA since CPLD's are small and SPI support is coming at a tight squeeze. I believe the Zorro-III 32bit memory address window is a true workaround to this problem. Fortunately for us, Stephen has done a lot of work in that area and it should go without saying that this hard work could be applied to the a1200 in some way or other. Well that's if the a1200 fingers at the trapdoor AND the PCI adapter by Kipper2k offers the necessary signals, I don't know.
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