` Setting bits in a Byte (Bob Roos ) - Icetips Article
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Par2: Setting bits in a Byte
2011-08-18 -- Bob Roos
 
variable = bor(variable,01h) ! turns on the right most bit variable = band(variable,0FEh) ! turns it off variable = bxor(variable,01h) ! flips it Bruce Johnson adds: x = BOR(x,SomeBit) ! turn it on x = XBOR(x,SomeBit) ! flip it x = BAND(x,255-SomeBit) ! turn it off a couple of things I like to do here; a) use an EQUATE to name the bit and b) Use "binary" number syntax. Consider for example the following; Bit0 Equate(00000001b) Bit1 Equate(00000010b) Bit2 Equate(00000100b) Bit3 Equate(00001000b) Bit4 Equate(00010000b) Bit5 Equate(00100000b) Bit6 Equate(01000000b) Bit7 Equate(10000000b) BitMax Equate(11111111b) using the 'b' numbering format it's easy to see where the bit falls in the sequence. And if say Bit3 and Bit4 always work together you can add an equate ControlBits Equate(00011000b) and so on. this allows yor code to be quite readable - for example x = Bor(x,Bit3+Bit6) ! turn on Bit 3 and Bit 6 x = Bxor(Bit2) ! flip bit 2 x = Band(BitMax-Bit7-Bit1) ! turn off bit 7 and bit 1 The only consideration you should really have to worry about is whether you count the bits as bit 1 to bit 8, or bit 0 to bit 7. That can go both ways, but usually I code it to match the documentation I'm working from. If it's my decision I'll use Bit 1 so it's consistent with the rest of Clarion.


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