Ldcpi/ldepi – Samsung S3F80JB User Manual

Page 185

Advertising
background image

S3F80JB

INSTRUCTION SET

6-57

LDCPI/LDEPI

Load Memory with Pre-Increment

LDCPI/
LDEPI

dst,src

Operation: rr

← rr + 1

dst

← src

These instructions are used for block transfers of data from program or data memory from 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

← RR6 + 1)

; 7FH (contents of R0) is loaded into program memory

; location 2200H (21FFH + 1H)

; R0 = 7FH, R6 = 22H, R7 = 00H

LDEPI @RR6,R0

;

(RR6

← RR6 + 1)

; 7FH (contents of R0) is loaded into external data memory

; location 2200H (21FFH + 1H)

; R0 = 7FH, R6 = 22H, R7 = 00H

Advertising