Fill Memory Block (Fill) - Motorola CPU32 Reference Manual

7.2.8.11 Fill Memory Block (FILL)

FILL is used in conjunction with the WRITE command to fill large blocks of memory.
An initial WRITE is executed to set up the starting address of the block and to supply
the first operand. Subsequent operands are written with the FILL command. The initial
address is incremented by the operand size (1, 2, or 4) and is saved in a temporary
register. Subsequent FILL commands use this address, increment it by the current op-
erand size, and store the updated address back in the temporary register.
The FILL command does not check for a valid address in the tempo-
rary register — FILL is a valid command only when preceded by an-
other FILL or by a WRITE command. Otherwise, the results are
undefined. The NOP command can be used for inter-command pad-
ding without corrupting the address pointer.
The size field is examined each time a FILL command is given, allowing the operand
size to be altered dynamically.
Command Format:
15 14 13
0 0 0
Command Sequence:
FILL (B/W)
???
FILL (LONG)
???
Operand Data:
A single operand is data to be written to the memory location. Byte data is trans-
mitted as a 16-bit word, justified in the least significant byte; 16- and 32-bit oper-
ands 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.
CPU32
REFERENCE MANUAL
12 11 10 9
1 1 1 0
WRITE
DATA
MEMORY
"NOT READY"
LOCATION
XXX NEXT CMD
"ILLEGAL" "NOT READY"
MS DATA LS DATA
"NOT READY" "NOT READY"
XXX NEXT CMD
"ILLEGAL" "NOT READY"
DEVELOPMENT SUPPORT
NOTE
8 7 6 5
0 OP SIZE 0
XXX
"NOT READY"
NEXT CMD
"CMD COMPLETE"
XXX
BERR/AERR
WRITE
MEMORY
"NOT READY"
LOCATION
"CMD COMPLETE"
4 3
0 0 0 0
NEXT CMD
"NOT READY"
XXX
NEXT CMD
XXX NEXT CMD
BERR/AERR "NOT READY"
MOTOROLA
0
0
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