I have a working Data I/O 29B with a 128K RAM module
which only had
half of the DRAM sockets populated. From looking at the schematic, it
seemed that by simply populating the remaining DRAM sockets that I
would bring the module up to the full 128K. I tried that, but the 29B
still only reports 64K of RAM. What did I miss?
One of the manuals that I have says that the expansion board provides up
to 64K of memory, and that "future expansion" will allow up to 128k of
memory.
Later on, it says: "64K or 128K (future) configuration is selected by
the programming of PAL, U22". So this could be one issue.
It could also be firmware related - you probably want to have the latest
firmware installed (IIRC 6?). Later versions of the 29B supported up to
256K of RAM.
Dave
--
dave06a (at) Dave Dunfield
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