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S3C84E5/C84E9/P84E9 INSTRUCTION SET
6-57
LDCPI/LDEPI — Load Memory with Pre-Increment
LDCPI dst,src
LDEPI dst,src
Operation: rr ← rr + 1
dst ← src
These instructions are used for block transfers of data from program or data memory to the register
file. The address of the memory location is specified by a working register pair and is first
incremented. The contents of the source location are loaded into the destination location. The
contents of the source are unaffected.
LDCPI refers to program memory and LDEPI refers to external data memory. The assembler makes
"Irr" an even number for program memory and an odd number for data memory.
Flags: No flags are affected.
Format:
Bytes Cycles Opcode
(Hex)
Addr Mode
dst src
opc src | dst 2 14 F3 Irr r
Examples: Given: R0 = 7FH, R6 = 21H, and R7 = 0FFH:
LDCPI @RR6,R0 ; (RR6 ← bRR6 + 1)
; 7FH (the contents of R0) is loaded into program memory
; location 2200H (21FFH + 1H);
; R0 = 7FH, R6 = 22H, R7 = 00H
LDEPI @RR6,R0 ; (RR6 ← bRR6 + 1)
; 7FH (the contents of R0) is loaded into external data
memory
; location 2200H (21FFH + 1H);
; R0 = 7FH, R6 = 22H, R7 = 00H
NOTE: LDEPI instruction can be used to read/write the data of 64-Kbyte data memory.