Hyundai GMS800, Instruction Manual

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HYUNDAI MicroElectonics
24
BEQ
( Branch if equal )
Function : if (Z) = 1, then ( PC ) ( PC ) + rel
Description : Branches if zero flag is “1”.
Flag
:
Mnemonic OP Code Bytes Cycles
BEQ rel
F0 2 2/4
Example :
115 E085 C4C0 LDA #0C0H ; READ R0 PORT DATA
116 E087 3E07 LDY #7H ; 8 TIMES LOOP COUNTER
117 E089 08 LOOP: ASL A
118 E08A 5003 BCC KISTATUS
119 E08C BE DEC Y ; Y-1 -> Y
120 E08D F0FA BEQ LOOP
121 E08F C400 KISTATUS: LDA #0
BIT
( Bit test )
Function : ( Z ) ( A ) ( M )
( N ) ( M
7
) , ( V ) ( M
6
)
Description : Logical AND of the accumulator and the contents of memory.
The result effects zero flag(Z) and the bit7 of memory enter into negative flag(N), bit6 enter
into overflow flag(V).The accumulator and the contents of memory are unchanged.
Flag : M
7
M
6
Mnemonic OP Code Bytes Cycles
BIT dp 0C 2 4
BIT !abs 1C 3 5
Example :
97 E06F C40F LDA #0FH
98 E071 0C5C BIT 5CH
99 E073 F004 BEQ JMP_NXT
100 E075 2130 SET1 30H.1
101 E077 2F02 BRA MEMCOM1
102 E079 3130 JMP_NXT: CLR1 30H.1
103 E07B FF MEMCOM1: NOP