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PC-DOS 3.2 for 5150

Yeah, that's a straight up bug in the 8019AS chipset, you're not supposed to qualify memory accesses on AEN like I/O accesses. But of course it's not going to matter with a boot ROM unless you're doing something extremely weird.
Also tried with AS6C1008 SRAM without success. I noticed that it differs from AS6C4008 pinout (#1: NC instead of A18 and #30: CE2 instead of A17). Any ideas?
Best regards
 
Also tried with AS6C1008 SRAM without success. I noticed that it differs from AS6C4008 pinout (#1: NC instead of A18 and #30: CE2 instead of A17). Any ideas?
Best regards
I use AS6C1008 SRAM on my network card. With #30: CE2 connected to +5V, #1: NC and #2: A16 connected to ground I have 64Kb of upper memory.
 
Which network card do you own? I use this: https://github.com/hkzlab/ISA_8bitNetwork_8019

I haven't confirmed by looking at the card schematic (not in a place where I can load it into kicad and the repo doesn't seem to have a PDF/image version), but since the card was set up for a SST39SF040 I would guess you're going to have to fix the following things:

A: You'll need to swap pins 31 and 29, as previously needed for the AS6C4008
B: You'll need to cut pin #30 loose from A17 and pull it up to +5v.

"B" is necessary because CE2 is active high, unlike CE's active low. A17 is going to be low when accessing the first 128K of memory in the socket. You could possibly work around this by programming the pager on the 8019 to map in 64K from an address with A17 high, but I don't *think* the driver in the repo adjusts/sets the memory page so you'll have to look at the datasheet to figure that part out. Probably easier to just cut the trace or leave that pin of the SRAM out of the socket to wire it to +5v.
 
FIY, I have updated the code of RTL2UMB in the github repo. The new code sets up the data and stack segment correclty, and can be compiled with Borland's TASM on MS/PC-DOS, with Watcom's WASM on modern machines, and possibly also with MASM.
 
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