This file contains the putchar function which is the low-level character output routine for the stream I/O routines. All stream routines that output character data do so through this routine. You may adapt this routine to your individual hardware (e.g., LCD or LED displays).
The default PUTCHAR.C file delivered with the C51 compiler outputs characters via the serial interface. An XON/XOFF protocol is used for flow control. Linefeed characters (\n) are automatically converted into carriage return/linefeed sequences (\r \n).