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Dec rr, Operation, Description – Zilog EZ80F916 User Manual

Page 147: Condition bits affected, Attributes

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eZ80

®

CPU

User Manual

UM007715-0415

CPU Instruction Set

138

DEC rr

Decrement

Operation

rr

rr – 1

Description

The rr operand is any of the multibyte CPU registers BC, DE, or HL. The value contained

in the specified register is decremented by 1.

Condition Bits Affected

None.

Attributes

kk

identifies the BC, DE, or HL register and is assembled into one of the opcodes indi-

cated in

Table 53

.

Mnemonic

Operand

ADL Mode

Cycle

Opcode (hex)

DEC

rr

X

1

kk

DEC.S

rr

1

2

52, kk

DEC

.L

rr

0

2

49, kk

Table 53. Register and kk Opcodes for DEC rr Instruction (hex)

Register kk

BC

0B

DE

1B

HL

2B

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