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MICROPROCESSOR INSTRUCTION REFERENCE->BCLR
BCLR Test a Bit and Clear
Complement of (<bit no.> Destination) -> Z
0 -> (<bit no.> Destination)
| Assembler Syntax: | BCLR Dn,<ea> |
| BCLR #<data>,<ea> |
Dn or #<data> specify the bit number
Size: Byte, Long
Tests a bit in the destination operand and sets the Z condition code appropriately, then clears the specified bit in the destination. When a data register is the destination, any of the 32 bits can be specified by a modulo 32-bit number. When a memory location is the destination, the operation is a byte operation, and the bit number is modulo 8.. In all cases, bit zero refers to the least significant bit.
If <ea> is Data register then #<data> 0 - 31 else #<data> 0 - 7
Condition Codes:
N Not affected
Z Set if bit tested = 0, else clear
V Not affected
C Not affected
X Not affected
| Allowable Addressing Modes |
|
| Dn,Dn | #(data),Dn |
| Dn,(An) | #(data),(An) |
| Dn,(An)+ | #(data),(An)+ |
| Dn,-(An) | #(data),-(An) |
| Dn,(d16,An) | #(data),(d16,An) |
| Dn,(d8,An,Xn) | |
| Dn,(xxx).W | |
| | Dn,(xxx).L | |
Dn,Dn and #(data),Dn are long only; all others are byte only.