In the above image, you can see where I have begun to test the control signals on the Micro. An old Thandar Logic Analyser TA100 was used to test these signals. Any modern logic analyser would also work, but I’m trying to keep this retro, or maybe I was just too lazy to plug in a USB logic analyser to my laptop and set it all up. I’ll let you decide.
You can see in the picture that the Micro’s clock E, the Read/Write line and the address strobe line, have been brought out of the Micro. The E and Read/Write line are inputs to the 74HC00 NAND gate logic, which is generating both a Read Enable and Write Enable signal, both of which are active low.
I’ll upload a quick video on these control signals when testing the address decoder logic.
All initial tests pass with no issues. So far so good.