Question

With a suitable diagram,explain how clock is generated in 8085

Answer 1

Explanation:

As we know that RD (Read) is a control signal. Because this signal is used both for reading memory and for reading an input device, it is necessary to generate two different Read signal : one for memory read control signal and another for input read control signal. Similarly, two separate Write signal must be generated.

DIFFERENET CONTROL SIGNALS

Above Figure shows that four different control signals are generated by combining the signals RD, WR and IO/M. The signal IO/M goes low for the memory operation. This signal is ANDed with RD and WR signals by using bubbled input NAND gates