[SOLVED] MAX 485 with 8051 communication (RS485)

[torana]

i am very new to RS485. I came to know that both RS232 and RS 485 coding is same. Is it correct !
I am going to communicate 4 MCU (8051). but i am confuse with following

how to send address and data.
what will be H/W diagram
how to program for data transfer speed .

 

[deebar]

I think RS232 and RS485 coding is not the same, because when coding for RS485, you should manually switch between the transmitter mode and receiver mode by setting relevant signal lines.

if you want to communicate multiple MCUs utilizing RS485, you can take a look at MODBUS. Hope it will help you.

 

[Debasis Swain]

www.circuitcellar.com
pls refer the above site for your problem from which you can find your problem relating rs485.
i think the code is same for rs232 and rs485 but the transmitter/receiver signal line(pin no.2&3 of rs485)should specify either transmit or receive,for transmit it should connect with 5v and for receive it connect with gnd.

 

[debabrta kar]

yes code for both rs232 and rs485 is same but in rs 485 we have to switch the direction of control pin of max485 for transmit and receive