Hi,
I want to use an external EPROM for program memory. I've connected the EA pin to ground and I've loaded the code onto the EPROM(I've checked the contents in Proteus and it's correct). The problem is, when I run the simulation in Proteus without a program file for 8031 itself, nothing happens. I mean the address bits on port 0 and 2 get stuck at 0xFFFF and ALE and PSEN are also stuck at 1. If I load the program file on 8031, the code runs ok, however port 0 and 2 still don't output the address and increment it as needed. (Again stuck at 0xFFFF but this time ALE works fine and makes port 0 float as ALE is pulled down). What am I doing wrong?!
I want to use an external EPROM for program memory. I've connected the EA pin to ground and I've loaded the code onto the EPROM(I've checked the contents in Proteus and it's correct). The problem is, when I run the simulation in Proteus without a program file for 8031 itself, nothing happens. I mean the address bits on port 0 and 2 get stuck at 0xFFFF and ALE and PSEN are also stuck at 1. If I load the program file on 8031, the code runs ok, however port 0 and 2 still don't output the address and increment it as needed. (Again stuck at 0xFFFF but this time ALE works fine and makes port 0 float as ALE is pulled down). What am I doing wrong?!
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