We have to watch port0 and port3 to obtain the information about external data memory access using Keil. However, the problem is that we can't see the change in port3(RD# or WR# should have changed) during external data memory access in the watch window of Keil. Can we see the change of a VTR or an SFR in a machine circle? Any help will be greatly appreciated! Thanks a lot! I'm waiting for the reply on line.