Re: Communication Problem:: RS-485 (MASTER) and RS-485(SLAVE
Thank you guys for your help.
By the way, I think I forgot to mention the following parameters of my system:
1. Baud rate = 38,400 bits/sec
2. Max. Number of allowable slaves is 4.
3. Connection of about 1000 meter cable (maybe shielded twisted pair)
4. Since I have not tested my devices for a long range, so I could not tell you if my termination is working or not. I am using 120 ohm termination resistors. None the less I think I will use weak pull-up and pull down resistors, just to maintain stability at all time.
5. I thought that by enabling and disabling the transmitter on the PICs, you would be flushing the USART. I will read the manual again for PIC and see if this is true.
This picture shows the control Line RC5 (CH2), and the outgoing data on line A (CH1).
This picture shows the Control line RC5 (CH2), and incoming data on RC7 (RX)
[MASTER side].