Task-Specific Program Code
C-22
Example C–14. Using Synchronous Serial Port With Codec Device (ad55.asm)
(Continued)
codtx:
splk
#0010h, ifr
; clear tx intr flag
clrc
intm
ret
codrx:
setc
xf
; toggle xf bit
in
*,sdtr
; Read ADC value
lacc
*+,0
; Make LSB zero
and
#0fffeh,0
; to avoid secondary
sacl
6ah,0
; request for codec
out
6ah,sdtr
; Send ADC value to DAC
mar
*,ar0
banz
skip,ar1
; Check buffer limits
lar
ar1,#rxbuf
lar
ar0,#size
skip:
splk
#0008h, ifr
; Clear ifr flag
clrc
intm
ret
inpt1:
ret
inpt23:
ret
timer:
ret
uart:
ret
.end
; Assembler module end directive
; –optional