Quote:
Originally Posted by SiriusHardware
Quote:
Originally Posted by Duke_Nukem
If nothing else fill a ROM with NOP instructions (0x90 hex), you should then at least see consistant signals on the address line as the processor walks through the ROM.
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Not too sure about that value, DN - I thought NOP in 8085 and Z80 was 0x00?
I would, also, make the third last byte in the eprom 0xC3 so that the last three bytes at the top end are C3 00 00, meaning, 'Jump back to address 0000'. |
You are right, it is 0x00 for NOP ! Funny thing, I was typing whilst whilst waiting for a course to restart after lunch so I was sat there in a room with 7 other programmers, it was someone else that looked up the value (my google searches gave plenty of hints telling me what NOP was but not the op-code). (The young-uns were looking up "what's an 8085" and "what's an opcode"
).
Anyhow, writing minimal programs that loop while doing one specific thing is a way to tackle tracking down whats working or not.
TTFN,
Jon