Friday, 7 December 2012

How to Demultiplex Address and Data Bus

Generally, 74LS373 Latch IC is used for latching the address issued by Microprocessor.
It has 8-latches(D-flip flop).

Address will
 appear on AD0-AD7 lines.
ALE will go high and forcing enable G pin of Latch. This will make the latch transparent. It means whatever will be input, will be output. Presently input address is A0-A7.Therefore output is A0-A7.
When ALE=0, then AD0-AD7 will now be used as data bus.