Hello, I'm trying to pass a variable to a function, but the value stored in the variable never arrives. When I pass a constant, however, the value is handed over. An example follows: main.c extern void TransmitHex( unsigned char hexval ); main{ unsigned char var; var = 0x41; TransmitHex( 0x41 ); // produces an "A" in ASCII TransmitHex( var ); // nothing shows up, possibly 0x00 is transmitted } --- serial.c void TransmitHex ( unsigned char hexval){ /* transmit hexval via serial port */ } I've tried to locate var with NEAR and FAR, but the problem persists. I'm using the HLARGE memory model. I have an external RAM connected to the ST10, address window is configured properly. any ideas? regards, Soenke