Hello, I'm trying to write a Function that reads a character from RS232 (trival?). I'm using 80c552, Serial_Mode=1. I think the baudrate is set correct (I can transmit data to the PC). The Problem is, S0BUF is allways empty. I tried it on the simulator too. I paste my code:
CLR RI JNB RI,$ ; waiting for character MOV R7, S0BUF ; <- here S0BUF is ALLWAYS 0x00 RET
Any ideas? I thought Serial i/o will be trival... Often the most mundane will give you the strangest effects 1) have you scoped on RxD? 2) Is REN in SCON set? Erik
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