I changed to 89c55WD from 89c52 due to more code space but my RAM (62256) stopped responding. When I try to read RAM I always get 0xFF. I just have 89c55WD, 62256 and 74LS373 on my board. I tried changing the Ic and boards but problem is still there. I am using 10k+10uf reset circuit.
I am not able to understand the problem is it due to Reset circuit ?? if yes then what is ideal circuit for reset. Also is it necessary to pull EA with a high resistance

Yash