National Instruments Corporation GPIB-1014P User Manual page 130

Sample Programs
68000 Code
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DSEND: link a6,-8
movl d1,a6@(-4)
movl d2,a6@(-8)
movl d0,d1
DSEND1: movb ISR1.L,d2
btst #DO=ERR,d2
beq DSEND1
btst #ERR,d2
bne DSEND3
subl #1,d1
bmi DSEND4
bne DSEND2
cmpb #0,vseoi.L
beq DSEND2
movb #SEOI,AUXMR.L
DSEND2: movb a0@,CDOR.L
bra DSEND1
movb #DMAO,IMR2
DSEND3: movl #-1,d0
DSEND4: movl a6@(-8),d2
movl a6@(-4),d1
unlk a6
rts
GPIB-1014P User Manual
|
| Comments
|
| Link
| Save d1
| Save d12
| Copy byte count
|
| Wait for CDOR or ERR
|
| Look for error
|
| dec byte counter
| Have all bytes been sent?
| No–Is this last byte?
| Yes–EOI in use?
| No
| Send EOI with last byte
| Next byte
|
| Enable DMA to the CDOR
| Return (-1) indicating error
| Restore d2
| Restore d1
| Unlink
| Return
C-14
Appendix C
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