To set bit 4 on and leave the rest unchanged:

mybyte=mybyte | %00010000 'OR function with selected bit masked ON

To turn bit 4 off and leave the rest unchanged:

mybyte=mybyte & %11101111 'AND function with selected bit masked OFF

OR you can set multiple bits on or off by either ADDING or SUBTRACTING the bit weight to/from either 0 or 255 respectively.

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