4K7 seems to be a bit on the high side, I have always used 2k2 for my pullups. Maybe a reason?
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Re: 18F4420 and 1-Wire
4K7 seems to be a bit on the high side, I have always used 2k2 for my pullups. Maybe a reason?
Dave Purola,
N8NTA
EN82fn
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Re: 18F4420 and 1-Wire
The datasheet calls for a "strong" pull-up and recommends 4K7; I searched the internet and saw others having success with this value. I have no knowledge or experience that suggests a better value, so I tried it and it seems to work well.
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Re: 18F4420 and 1-Wire
a very good reason is the cable length between the probe and the PCB ....Originally Posted by Dave
Alain
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Why insist on using 32 Bits when you're not even able to deal with the first 8 ones ??? ehhhhhh ...
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IF there is the word "Problem" in your question ...
certainly the answer is " RTFM " or " RTFDataSheet " !!!
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Re: 18F4420 and 1-Wire
I haven't tested with long wires yet:
http://www.picbasic.co.uk/forum/showthread.php?t=17282
but 4K7 worked at 115,200 at 64MHz in preliminary tests.
(Diagram in post #1 is not updated, only 2 resistors used)
Robert
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Re: 18F4420 and 1-Wire
115,200.... What?
Dave Purola,
N8NTA
EN82fn
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Re: 18F4420 and 1-Wire
Actually the main reason for lower value resistors is when there are several devices on the bus. If you are just using one device, 4.7 K is fine and wastes less current.
Robert, you must have posted on the wrong thread? No RS-232 in this discussion...
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Re: 18F4420 and 1-Wire
Oops. Overly medicated apparently. LOL
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