h6. [[OS SWI Calls]] h6(. » [[OS_Byte]] h6((. » OS_Byte 203 h2. OS_Byte 203 h5. (SWI &06) |_<^{width:4em}. Entry | | |<^. R0|<^. 203 (&CB) | |<^. R1|<^. EOR value | |<^. R2|<^. AND value | |_<^{width:4em}. Exit|_<^. | |<^. R0|<^. Preserved | |<^. R1|<^. Value before being overwritten | |<^. R2|<^. Serial ignore flag (see [[OS_Byte 204]]) | h4. Use The purpose of this call is to read or write the serial buffer threshold. h4. Notes This call reads or sets the serial buffer threshold. While the free space is below this value the serial hardware will attempt to halt incoming data. [[OS_SerialOp 0]] controls the handshaking method. The default threshold is 9 characters. h4. See also * [[OS_Byte]] * [[OS_Byte 204]] * [[OS_SerialOp 0]]