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Interface 2 PICS 16F877A use MAX485

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NamNQ

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Dear all!
I am a noob of PIC! and now i have a problem!
I want to connect two PICS. I use Proteus and C CSS.
I try connect them directly by connect RC6/TX(1) <-> RC7/RX(2) and RC7(1) <->RC6(2). It working corectly. (I 've read a example and i can understand it).
Then, i want to connect them via max487 instead of max485. Sorry, i can't find max485 in proteus.
Now, i dont understand how to interface and code them!
Could you teach me how to resole this problem!
Thank you, thank so much!
Best regards !
 

Hi there, have you read the datasheet for MAX485. It is a simple IC to ineterface. All you have to do is to select DE or RE to Read and write data. But before using read some material from the following link.
**broken link removed**

enjoy!
 
Hi there, have you read the datasheet for MAX485. It is a simple IC to ineterface. All you have to do is to select DE or RE to Read and write data. But before using read some material from the following link.
**broken link removed**

enjoy!

Thank Babar_Ali. I know RS485 use half-duplex trans. I 've been reading RS485.c and EX_RS485.c in CCS library.
I think, i must read about interrupt first (sorry for my noob).
Anyway, to save time, could you send me a easy example for RS485 (init, send and receive data...)?
My datagram :
rs485dg_zpsee1b8e3f.png

Best regards!
 
Hi there,

I never used CCS compiler. I have done work with HITEC PICC compiler.
You are right you must read about the serial interrupt. One thing that i noticed is that you have not used pull up resistors to the diffrential pair data lines. Find the attached image for details.

Also here is a chunk of code that I used to transmit data from one device to another.
Code:
unsigned char SerIn()
{
   DIR = 0;   // RS485 chip to Rx mode
   /* your code goes here*/
    return  UARTDATA; // Read Data if there is no parity or framing error.
}

void SendSerial(char data485)
{
DIR = 1;   // RS485 chip to TX mode
TX = data485;
}
 

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