Communication Between Two PIC Controllers

hi,

i want to interface two pic controllers for information or command exchange serially which are separated with each other for let say 20 to 50 meters.. so i want to use rs485 standard...
can any one help me up how can i design hardware for this...


regards,
sagar mengar

hi,

first u hav to learn the rs485 protcol........ which has master & slave concepts...... hard ware is standard so don wan to worry on it.... use max485

thnks pravin,

okey i got yr point,
can u suggest me some reference document on rs485 which is good for understanding and easy to learn....

thnks a lot brother....!!!

regards,
sagar

hii.....

learn this pdf fully u can understand about modbus protocol............. if u hav any clarifications.... feel free to ask me........

hello, i am starting programming programs whitch communicate between two pic18f6520. (it is possible to use spi also, but what is maximum cable lenght between spi devices?) the protocol should be very easy. it will be send only 2-4 bytes at o...

hi,

it will support only for maximum 4mtrs...........