Apple II manual Inr, Bnc, Bnz, BM1, BNM1, Example SET R5, Load, Store

Models: II

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En

INR

Rn

(Increment)

Fn

DCR

Rn

(Decrement)

Non-register OPS-

 

 

00

RTN

 

(Return to 6502 mode)

01

BR

ea

(Branch always)

02

BNC

ea

(Branch if No Carry)

03

BC

ea

(Branch if Carry)

04

BP

ea

(Branch if Plus)

05

BM

ea

(Branch if Minus)

06

BZ

ea

(Branch if Zero)

07

BNZ

ea

(Branch if NonZero)

08

BM1

ea

(Branch if Minus 1)

09

BNM1

ea

(Branch if Not Minus 1)

0A

BK

 

(Break)

0B

RS

 

(Return from Subroutine)

0C

BS

ea

(Branch to Subroutine)

0D

 

 

(Unassigned)

0E

 

 

(Unassigned)

0F

 

 

(Unassigned)

Register Instructions:

 

 

----------------------

 

 

SET:

 

 

 

SET Rn,Constant

[ 1n Low High ]

The 2-byte constant is loaded into Rn (n=0 to F, Hex) and branch conditions set accordingly. The carry is cleared.

EXAMPLE:

15 34

A0

SET R5

$A034

;R5 now contains $A034

LOAD:

 

 

 

 

LD Rn

 

 

[ 2n ]

 

The ACC (R0) is loaded from Rn and branch conditions set according to the data transferred. The carry is cleared and contents of Rn are not disturbed.

EXAMPLE:

15

34

A0

SET

R5

$A034

25

 

 

LD

R5

;ACC now contains $A034

STORE:

 

 

 

 

 

ST Rn

 

 

 

[ 3n ]

The ACC is stored into Rn and branch conditions set according to the data transferred. The carry is cleared and the ACC contents are not disturbed.

Page 45
Image 45
Apple II manual Inr, Bnc, Bnz, BM1, BNM1, Example SET R5, Load, Store