Obviously setting, or clearing a bit is done with bsf and bcf. Toggleing a bit is done with XOR and a mask. But what if you don't know which bit to set, clear or toggle before the program is compiled?
There are two ways of implementing this operation based on where the input value is relative to the output value. If they are the same (ie the operation is to complement a specific bit), the code to be used is simply:movlw 1 << BitNumber ; Complement Specific Bit for "NOT" xorwf BitRegister, f
If the bit is in another register, then the value stored is the complement of it:bcf Result ; Assume that the Input Bit is Set btfss Bit ; - If it is Set, then Result Correct bsf Result ; Input Bit Reset, Set the Result
|file: /Techref/microchip/math/bit/flipbit.htm, 1KB, , updated: 2004/12/6 12:55, local time: 2018/7/18 02:21,
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