Samsung F8274X Computer Hardware User Manual


 
INSTRUCTION SET S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X
6-58
LDW Load Word
LDW dst,src
Operation: dst src
The contents of the source (a word) are loaded into the destination. The contents of the source
are unaffected.
Flags: No flags are affected.
Format:
Bytes Cycles Opcode
(Hex)
Addr Mode
dst
src
opc src dst 3 8 C4 RR RR
8 C5 RR IR
opc dst src 4 8 C6 RR IML
Examples: Given: R4 = 06H, R5 = 1CH, R6 = 05H, R7 = 02H, register 00H = 1AH,
register 01H = 02H, register 02H = 03H, and register 03H = 0FH:
LDW RR6,RR4 R6 = 06H, R7 = 1CH, R4 = 06H, R5 = 1CH
LDW 00H,02H Register 00H = 03H, register 01H = 0FH,
register 02H = 03H, register 03H = 0FH
LDW RR2,@R7 R2 = 03H, R3 = 0FH,
LDW 04H,@01H Register 04H = 03H, register 05H = 0FH
LDW RR6,#1234H R6 = 12H, R7 = 34H
LDW 02H,#0FEDH Register 02H = 0FH, register 03H = 0EDH
In the second example, please note that the statement "LDW 00H,02H" loads the contents of
the source word 02H, 03H into the destination word 00H, 01H. This leaves the value 03H in
general register 00H and the value 0FH in register 01H.
The other examples show how to use the LDW instruction with various addressing modes and
formats.