1. Branching and Loops

2. Jumping
Jump instruction causes a change in the program flow to any location within the addressable range of the processor.
ORG $0200
AC LDAA #$AC
E 02 0B JMP STORE
F CLRA
F CLRB
F CLR $0200
020A ASRA
020B B STORE STAA $0250
020E 7E 02 0E END JMP END

3. Jump
ORG $ AC LDAA #$AC E 02 0B JMP $020b F CLRA F CLRB F CLR $ A 47 ASRA 020B B STAA $ E 7E 02 0E JMP $020e

4. Branching and Relative Address Mode
Branch instructions differ from the jump instructions in that they do not supply the absolute address of the next instruction.

5. Branching and Relative Address Mode
BCC
BCS
BEQ
BMI
BNE
BPL
BVC
BVS
BHS
BLO

6. Branching and Relative Address Mode
ORG $ AC LDAA $AC A 05 BPL POS 0204 B STAA $ BRA END 0209 B POS STAA $ C 20 FE END BRA END

7. Destination address calculation
Problem: Calculate the destination address (DA) for each of the following branch instructions.
ADDRESS MACHINE CODE SOURCE CODE
C BRA PAST
O1F7 20D3 BRA LOOP
063A 20 9B BRA AGAIN

8. RELATIVE ADRESS (rr) CALCULATION
Calculate the relative address (rr) for each of the following branch instuctions a. ORG $ AC LDAA $AC A ?? BPL POS 0204 B STAA $ ?? BRA END 0209 B POS STAA $ C 20 ?? END BRA END

9. RELATIVE ADRESS (rr) CALCULATION
ORG $ AC LDAA $AC B AD ADDA $AD ?? BVS ERROR ?? BCS CARRY 0308 B STAA $ B 20 ?? BRA END 030D CARRY LDAA #$01 030F B STAA $ ?? BRA END 0314 CC FF FF ERROR LDD #$FFFF 0317 FD STD $ A 20 ?? END BRA END

10. Compare Instructions
CMPA
CMPB
CPD
CPX
CPY
CBA

11. Test Instructions
TSTA
TSTB
TST

12. IF-THEN-ELSE
ORG $0200
LDAA $03FA
BPL PAST
NEGA
PAST STAA $03FA

13. WHILE AND UNTIL LOOPS

14. TIMING LOOPS
$0200 LDX #100 LOOP DEX BNE LOOP

15. TIMING LOOPS LDAA #30 STAA $1000 LDAA #00 STAA $1001 BACK DEC $1001
                ORG     $0200
                LDAA     #30
                STAA        $1000
                LDAA     #00
                STAA     $1001
BACK     DEC     $1001
                BNE     BACK
                DEC     $1000