Specifications

Program Examples
B-14
;===========================================================================
;SCI TRANSMISSION TEST – starts here
;===========================================================================
SCI: LDP #0E1h
SPLK #0FFFFh,MCRA
LAR AR0, #SCITXBUF ;Load AR0 with SCI_TX_BUF address
LAR AR1, #SCIRXBUF ;Load AR1 with SCI_RX_BUF address
LAR AR2, #20h ;AR2 is the counter
LAR AR3, #60h ;AR3 is the pointer
LDP #SCICCR>>7
SPLK #17h, SCICCR ;17 for internal
;loopback 07–External
;1 stop bit,odd parity,8 char bits,
;async mode, idle–line protocol
SPLK #0003h, SCICTL1 ;Enable TX, RX, internal SCICLK,
;Disable RX ERR, SLEEP, TXWAKE
SPLK #0000h, SCICTL2 ;Disable RX & TX INTs
SPLK #0000h, SCIHBAUD
SPLK #0186h, SCILBAUD ;Baud Rate=9600 b/s (30 MHz SYSCLK)
LDP #SCICCR>>7
SPLK #0023h, SCICTL1 ;Relinquish SCI from Reset.
XMIT_CHAR: LACL #55h ;Load ACC with xmit character
MAR *,AR0
SACL *,AR1 ;Write xmit char to TX buffer
LDP #SCICTL2>>7
XMIT_RDY: BIT SCICTL2,BIT7 ;Test TXRDY bit
BCND XMIT_RDY,NTC ;If TXRDY=0,then repeat loop
RCV_RDY: BIT SCIRXST,BIT6 ;Test TXRDY bit
BCND RCV_RDY,NTC ;If TXRDY=0,then repeat loop
READ_CHR: LACL *,AR3 ;The received (echoed) character is
;stored in 60h
SACL *+,AR2 ;This loop is executed 20h times
BANZ XMIT_CHAR ;Repeat the loop again
LOOP B LOOP ;Program idles here after executing
;transmit loops