h6. [[OS SWI Calls]] h6(. » OS_SerialOp h2. OS_SerialOp h5. (SWI &57) |_<^{width:4em}. Entry | | |<^. R0 |<^. "Reason code":#reason| |\2<^. All other registers dependent on reason code| |_<^{width:4em}. Exit | | |<^. R0 |<^. Preserved| |\2<^. All other registers dependent on reason code| h4. Use The purpose of this call is to access the serial device driver directly. h4. Notes The action performed depends on the reason code value in R0. OS_SerialOp is vectored via [[SerialV]]. h4(#reason). Reason Codes |_<^{width:4em}. #|_<^{width:4em}. Hex #|_<^. Action| |<^. 0|<^. &00|<^. [[OS_SerialOp 0|Read/write serial states]]| |<^. 1|<^. &01|<^. [[OS_SerialOp 1|Read/write data format]]| |<^. 2|<^. &02|<^. [[OS_SerialOp 2|Send break]]| |<^. 3|<^. &03|<^. [[OS_SerialOp 3|Send byte]]| |<^. 4|<^. &04|<^. [[OS_SerialOp 4|Get byte]]| |<^. 5|<^. &05|<^. [[OS_SerialOp 5|Read/write receive baud rate]]| |<^. 6|<^. &06|<^. [[OS_SerialOp 6|Read/write transmit baud rate]]| |<^. 7|<^. &07|<^. Internal use only| |<^. 8|<^. &08|<^. [[OS_SerialOp 8|Read/write serial input buffer threshold value]]| |<^. 9|<^. &09|<^. [[OS_SerialOp 9|Enumerate available serial port speeds]]| |<^. 10|<^. &0A|<^. [[OS_SerialOp 10|Get device name]]| h4. See also * [[Baud Rate Codes]] * [[SerialV]]