FIRST STEPS IN MACHINE CODE

OPCODES

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TESTING FLAGS

     
Symbols and flag values
    Flag   Flag = 1   Flag = 0
 
    C C (Carry) NC (No carry)
    Z Z (Zero) NZ (No zero)
    P/V PO (Parity odd) PE (Parity even)
    S P (Positive) M (Negative)
 
     
Valid operations, and their opcodes
Unconditional
Operation
        Conditional Operation
Flag:   C P/V Z S
 
JP (C3)   JP C (DA)   JP PO (E2)   JP Z (CA)   JP P (F2)
JP NC (D2) JP PE (EA) JP NZ (C2) JP M (FA)
 
JR (18) JR C (38) ------ JR Z (28) ------
JR NC (30) ------ JR NZ (20) ------
 
CALL (CD) CALL C (DC) CALL PO (E4) CALL Z (CC) CALL P (F4)
CALL NC (D4) CALL PE (EC) CALL NZ (C4) CALL M (FC)
 
RET (C9) RET C (D8) RET PO (E0) RET Z (C8) RET P (F0)
RET NC (D0) RET PE (E8) RET NZ (C0) RET M (F8)

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