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Old 4th Sep 2021, 2:03 am   #1
JohnBHanson
Heptode
 
Join Date: Aug 2009
Location: Worthing, Sussex, UK.
Posts: 661
Default Northstar Advantage owner needed to run program

I am investigating the actual memory layout of the video memory of the Northstar Advantage computer.

Most documentation state that the video memory is 20k which consists
of a bank of 16k and a bank of 4k (which is repeated four times).

However the circuit diagram of the video memory consists of two banks of 4116 memory chips which gives 32k.

I have written an emulator for the NorthStar Advantage and would like the memory layout to be correct.

To this end I have written a program in Z80 assembler to explore the video memory layout and would like an owner of a real hardware Advantage to run it
for me and let me know what the output is.

The program is written in z80 assembler language (built with m80/l80) and
I am happy to supply the program in source code as well as binary. It does
not write to disk but reports the results to the screen (And a printer if one
is connected by using control+p).

If anyone can help it would be nice.

Thanks.
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