SAM47 INSTRUCTION SET

KS57C2308/P2308/C2316/P2316

 

 

LDC — Load Code Byte

LDC

dst,src

 

 

 

 

 

 

 

 

Operation:

Operand

Operation Summary

Bytes

Cycles

 

 

 

 

 

 

EA,@WX

Load code byte from WX to EA

1

3

 

 

 

 

 

 

EA,@EA

Load code byte from EA to EA

1

3

 

 

 

 

 

Description: This instruction is used to load a byte from program memory into an extended accumulator. The address of the byte fetched is the 6 highest bit values in the program counter and the contents of an 8-bit working register (either WX or EA). The contents of the source are unaffected.

Operand

 

 

 

Binary Code

 

 

 

Operation Notation

 

 

 

 

 

 

 

 

 

 

 

 

EA,@WX

1

1

0

 

0

1

 

1

0

0

EA [PC13–8 + (WX)]

 

 

 

 

 

 

 

 

 

 

 

 

EA,@EA

1

1

0

 

0

1

 

0

0

0

EA [PC13–8 + (EA)]

 

 

 

 

 

 

 

 

 

 

 

 

Examples: 1. The following instructions will load one of four values defined by the define byte (DB) directive to the extended accumulator:

LD

EA,#00H

CALL

DISPLAY

JPS

MAIN

ORG

0500H

DB

66H

DB

77H

DB

88H

DB

99H

DISPLAY LDC

EA,@EA ; EA address 0500H = 66H

RET

 

If the instruction “LD EA,#01H” is executed in place of “LD EA,#00H”, The content of 0501H (77H) is loaded to the EA register. If “LD EA,#02H” is executed, the content of address 0502H

(88H) is loaded to EA.

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Samsung KS57C2308 manual LDC Load Code Byte, Ldc, Call Display JPS Main ORG, Display LDC