Well RAM is ruled out. I think I am dealing with a bad ROM. D3 off the ROM seems to have lots of 0's. Also I am told there are HALT instructions in the rom code but the /HALT pin never drops on the Z80. What ever code it is executing sure doesn't seem right. Sockets installed. Ordered a 2364 to 27c64 EPROM adapter from RETRO Innovations. Now to wait for the mailman 😴
Well I got some 27c64's.. it at least does /something/ now 😆
It verily appears to me that you're outputting with the horizontal & vertical transposed!
"I appreciate SDF but it's a general-purpose server and the name doesn't make it obvious that it's about art." - Eugen Rochko