can somebody help me out on how to interface an 8051 ic to a 8742 keyboard controller ic..?? i am connecting a keyboard through a ps2 connector to the board...this interface is controlled by 8742..how do i obtain the keys pressed at 8051?
when the dinosaurs roamed the earth, the 8742 was quite commonly used.
8742 keyboard controller ic the datasheet is dated 1991 the cheapest I can find is $49.99 which indicates a discontinued and now rare chip.
I think you have to go back to the "requirement provider" and say "WHY?"
Erik
"I think you have to go back to the "requirement provider" and say "WHY?""
easy: it could be a learning experience; it could be a one-off project from salvaged parts; it could be just for fun; or it could be for no reason. countless possibilities.
Exactly - which is precisely why the OP needs to state which of those possibilities actually applies here!
"Exactly - which is precisely why the OP needs to state which of those possibilities actually applies here!"
you have a point but I am not sure how it relates to his problem.
back to topic: interfacing to any device is fairly simple - you just need to understand how that device works and make your mcu talk to it that way.
The relation to the problem is that a lot of people pick the first solution they get to think about. That sometimes goes for the person creating the thread. And sometimes for the person who requested the job done.
By knowing the reason for using the chip, we will know if there is a valid reason for this extra glue or if there is actually a better reason for interfacing directly with the PS/2 connector.
The reason behind a design can greatly affect what answers we will write.