Maxim Integrated MAXQ Family Users Guide: MAXQ2010 Supplement - Manual (Page 58)

MAXQ Family User’s Guide:
MAXQ2010 Supplement
10-2
mainLoop:
call RxChar0
call TxChar0
jump mainLoop
;==============================================================================
;=
;= TxChar0 - Outputs a character to serial port 0.
;=
;= Inputs : Acc - Character to send.
;=
TxChar0:
move SBUF0, Acc ; Send character
TxChar0_Loop:
move C, SCON0.1 ; Check transmit flag
sjump NC, TxChar0_Loop ; Stall until last transmit has completed
move SCON0.1, #0 ; Clear the transmit flag
ret
;==============================================================================
;=
;= RxChar0 - Receives a character from serial port 0.
;=
;= Outputs : Acc - Character received.
;=
RxChar0:
move C, SCON0.0 ; Wait for receive flag to be set to 1
sjump NC, RxChar0
move Acc, SBUF0 ; Get received character
move SCON0.0, #0 ; Clear receive interrupt flag
ret