Internal 32K RAM mod - Help

[Proteus]

Hi Andy, well i tried HRINVADER and HRDEMO30. What kind of HIRES can i run? It is a bit confusing
Regards.

[Andy Rea]

in thoery anything thats WRX, but some WRX stuff (different depending on the program ) required memory in the 8-16K area. HRG-MS should work also.

try 25thanmi, puzzle99 and rezurrection from Bodo's site http://bodo4all.cwsurf.de/

Andy

[Proteus]

Will do. Thank you Andy.

[Proteus]

No luck, i have tried them all, and all of them show the same pixel corruption in the reserved memory area. It seems the only ones that work are the ones that run in the 1K area. Any more suggestions would be appreciated. Thanks.

[sirmorris]

For hires to work properly you need to factor the REFSH signal into the chip select logic. I'd check around that portion of the circuit.

C

[Proteus]

Hi sirmorris, do you use the same 32K schematics as i?
What do you mean by "factor the REFSH signal into the chip select logic"?

[sirmorris]

I have used this design in a machine and it worked well. Having reviewed the schematic I can see there's no REFRESH in the circuit so my arguments are invalid Please ignore me

[Andy Rea]

what i find a little confusing is if the 1Kwrx worked then it should be good for the rest....

what test equipment do you have Proteus ? access to a scope ?

Regards Andy

[Proteus]

Unfortunately i do not have a scope, just a multimeter and a logic probe.

[RetroTechie]

Also the M1 not circuit might not be working, perhaps the LS00 overheated when soldering, or you picked up /M1 / A15 in the wrong spot. Can you check what happens when you connect the SRAM's pin 1 to a power supply (GND or +5, either will do) instead of to the LS00?

Have you tried this? Results? Any change(s) you see, as opposed to the LS00 circuit connected to this SRAM pin?