Quickest way to get highest set bit on port in to a variable?
Hi.
I have eight sensors with digital output connected to a port and now I want to in the quickest way get only the highest set bit in to a variable.
if port = 110000
I want var = 000000
if port = 001111
I want var = 001000
So how can I do this in quickest(least amount of clock cycles) possible way?
Regards
/Matias
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Re: Quickest way to get highest set bit on port in to a variable?
look at NCD command to do what you asked, checkout AND && for your example, search for MASK: http://www.picbasic.co.uk/forum/show...highlight=mask
or you could use a lookup table
Last edited by Archangel; - 1st March 2015 at 09:59.
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Re: Quickest way to get highest set bit on port in to a variable?
What PIC device?
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Re: Quickest way to get highest set bit on port in to a variable?
It´s a PIC18F45K80Originally Posted by towlerg
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Re: Quickest way to get highest set bit on port in to a variable?
sorry can't write PIC assembler but something like
WReg= 8
Rotate Left f through Carry, 1
jump on carry, done
dec WReg
Rotate Left f through Carry, 1
jump on carry, done
etc...
or maybe BTFSC - BitTest, skip if clear
George
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Re: Quickest way to get highest set bit on port in to a variable?
To repeat, look up NCD in the manual. I think it does what you want.
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