you might find the ds18b20 at http://canada.newark.com/
you might find the ds18b20 at http://canada.newark.com/
the thing is you have not mention how fast you are running your PIC. I found that problem when I ran my pic18f4550 with 20HMz, all I read back from the ds18b20 are zero/not connected. If I lower the chip to 4HMz then I can read the temperature.
I don't know how to confirm this, the OWOUT and the OWIN command might be too fast for the ds18b20 to catch up with faster pic chip ?
Check http://www.findchips.com This shows 6 distributors that stock the 18B20.
Where are you located? I'll send you a used one (at least we know it's working)
if you spring for the postage.
But, before I wrote it off as bad, I would check with what KVLV just said. You might
try using a different I/O-pin, different oscillator speed, etc.
Try a timing test with say an LED on a port pin. Toggle it on & off. Does it toggle at the
speed you expect? If not, it could be a timing issue, and that would definitely be a problem
with 1-wire comms.
LCDOUT can sometimes work just fine. Even if you have the wrong oscillator speed declared.
So I would run a series of tests before I wrote the sensor off as bad. Just in case.
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