S3C84E5/C84E9/P84E9

INSTRUCTION SET

 

 

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:

opc

src dst

 

 

Bytes

Cycles

Opcode

Addr Mode

 

 

(Hex)

dst

src

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.

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Samsung S3C84E5 user manual LDCPI/LDEPI Load Memory with Pre-Increment, Ldcpi dst,src Ldepi dst,src, Operation rr ← rr +