Hello, I´m trying to connect my 8051 to another 8051 with P3.0 and P3.1 using UART, but I can´t, I dont know why?.....The way that I do is:
*Start UART in both Systems *Send data to the first 8051 (TXD-P3.1) *Receive data in the second 8051 (RXD-P3.0), Then I will send it to the P1 to view it on display
Help Please!!!!!!!!!!!
When you transmit data from a UART, it is irrelevant what receives that data - so you can test your tramsmission part by sending to hyperterminal, or similar.
The classic beginner's "Hello, World" program would be an ideal starting point for sending data...
Likewise, when you receive data into a UART, it is irrelevant what sent that data - so you can test your receive part by sending from hyperterminal, or similar.
When you have a working transmitter (tested against hyperterminal), and a working receiver (tested against hyperterminal), then - and only then - you can join the two together.
Don't try to do everything at once - you will have no idea which part(s) are failing.
Remember that you will need an RS232 Transceiver between the microcontroller and a PC COM port; Alternatively, use one of these: www.ftdichip.com/.../USBTTLSerial.htm (3V or 5V as appropriate)
Note that the uVision Simulator can direct its simulated UART output to a COM port, and take its simulated UART input from a COM port. See the uVision Manual for details...