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NEC 78K/0 Series User Manual

Page 77

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77

CHAPTER 5 EXPLANATION OF INSTRUCTIONS

User's Manual U12326EJ4V0UM

Rotate Left

ROL

Byte Data Rotation to the Left

[Instruction format]

ROL dst, cnt

[Operation]

(CY, dst

0

dst

7

, dst

m+1

dst

m

)

× one time

[Operand]

Mnemonic

Operand(dst,cnt)

ROL

A, 1

[Flag]

Z

AC

CY

×

[Description]

The destination operand (dst) contents specified by the 1st operand are rotated to the left just once.

The MSB (bit 7) contents are simultaneously rotated to LSB (bit 0) and transferred to the CY flag.

[Description example]

ROL A, 1; The A register contents are rotated to the left by one bit.

CY

0

7