Typewriter User Manual

MOTOROLA MC68340 USER’S MANUAL 5- 83
Command Sequence:
NEXT CMD
"NOT READY"
"NOT READY"
XXX
BERR/AERR
"CMD COMPLETE"
DATA
"NOT READY"
XXX
NEXT CMD
XXX
"ILLEGAL"
NEXT CMD
"NOT READY"
FILL (LONG)
???
WRITE
MEMORY
LOCATION
NEXT CMD
"NOT READY"
XXX
"NOT READY"
XXX
BERR/AERR
"CMD COMPLETE"
MS DATA
"NOT READY"
NEXT CMDXXX
"ILLEGAL"
NEXT CMD
"NOT READY"
LS DATA
"NOT READY"
WRITE
MEMORY
LOCATION
FILL (B/W)
???
Operand Data:
A single operand is data to be written to the memory location. Byte data is transmitted
as a 16-bit word, justified in the least significant byte; 16- and 32-bit operands are
transmitted as 16 and 32 bits, respectively.
Result Data:
Status is returned as in the WRITE command: $0FFFF for a successful operation and
$10001 for a bus or address error during write.
5.6.2.8.12 Resume Execution (GO). The pipeline is flushed and refilled before normal
instruction execution is resumed. Prefetching begins at the return PC and current privilege
level. If either the PC or SR is altered during BDM, the updated value of these registers is
used when prefetching commences.
NOTE
The processor exits BDM when a bus error or address error
occurs on the first instruction prefetch from the new PC—the
error is trapped as a normal mode exception. The stacked
value of the current PC may not be valid in this case,
depending on the state of the machine prior to entering BDM.
For address error, the PC does not reflect the true return PC.
Instead, the stacked fault address is the (odd) return PC.
Command Format:
1514131211109876543210
0000110000000000
Frees
cale Semiconductor,
I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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