Xycom XVME-400, Manual

Page: 42 / 83

XVME-400/40l/490/49I Manual
October, 1989
R0L.W
#8,D7
M0VE.B #12,(AO)
M0VE.B
D7,(AO)
M0VE.B #14,(AO)
M0VE.B
#2,(AO)
M0VE.B #14,(AO)
M0VE.B #3,(A0)
M0VE.B
M0VE.B
M0VE.B
M0VE.B
M0VE.B
M0VE.B
#15,(AO)
#0,(A0)
#3,(A0)
#%11000001,(A0)
#5,(AO)
#%l1101010,(A0)
* Set WR12: Low order
* Time constant
* Set WR14
* BRG source=PCLK
* Enable BRG
* Set WR15: Disable all external
* interrupts
* Enable receiver
* Enable transmitter
RTS
********************************************************************************
*
I This routine will transmit a byte in polled mode.
*
*
On entry:
*
A2 contains the address of the command
*
register
of
the SCC channel used for
*
transmitting.
*
*
D2.B contains the byte to be transmitted.
*
******************************************************************************
TPOLA
MOVEML DO/D 1 /A 1 ,-(SP)
TXPOLL M0VE.B (A2),DO
BTST #2,DO
BEQ.S TXPOLL
TXBFE M0VE.B D3,2(A2)
* Save registers
* Read the contents of RR0
* Is TX buffer empty?
* No, then poll again
* Yes, move character to transmit
* data register
TXIT MOVEML (SP)+,DO/Dl / A 1
RTS * Restore registers
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