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Jump – Zilog Z86193 User Manual

Page 195

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Z8

®

CPU

User Manual

UM001604-0108

Instruction Description

188

Jump

Syntax

JP cc, dst

Instruction Format

Operation

If cc (condition code) is true, then PC

dst

A conditional jump transfers Program Control to the destination address if the condition
specified by cc (condition code) is true. Otherwise, the instruction following the JP
instruction is executed. See

Condition Codes

on page 146 for a list of condition codes.

The unconditional jump simply replaces the contents of the Program Counter with the
contents of the register pair specified by the destination operand. Program Control then
passes to the instruction addressed by the PC.

Address mode IRR can be used to specify a 4-bit Working Register. In this format, the desti-
nation Working Register operand is specified by adding

1110b

(

Eh

) to the high nibble of

the operand. For example, if Working Register R12 (CH) is the destination operand, then

ECh

is used as the destination operand in the Op Code.

Example 1

If the Carry Flag is set, the statement:

JP C, 1520h

Op Code: 7D 15 20

Cycles

OPC (Hex)

Address Mode

dst

cc OPC

dst

12 If jump taken

ccD

DA

10 If jump not taken

cc = 0 to F

dst

dst

8

30

IRR

Flag

Description

C

Unaffected

Z

Unaffected

S

Unaffected

V

Unaffected

D

Unaffected

H

Unaffected

E

dst

Note: