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1  Forum 2005-2010 (read only) / Interfacing / Re: Arduino and 1-wire on: November 11, 2008, 08:38:15 pm
Sorry for the thread ressurection, but I appear to be having a problem similar to the one experienced by audas, except this problem occurs in my setup after a FIFTH DS1820 is added.  I'm using the code on the Learning/OneWire page.

Here is an example of what happens:

Four sensors connected:
R=10 F2 36 55 0 8 0 D0 P=1 31 0 4B 46 FF FF 2 10 72  CRC=72
R=10 8A 14 55 0 8 0 92 P=1 33 0 4B 46 FF FF 3 10 30  CRC=30
R=10 E3 73 55 0 8 0 87 P=1 32 0 4B 46 FF FF E 10 FA  CRC=FA
R=10 EF 4A 55 0 8 0 8D P=1 31 0 4B 46 FF FF 3 10 B6  CRC=B6
No more addresses.

Looks good...  Now, I add a fifth:
R=10 F4 31 55 0 8 0 33 P=1 41 0 4B 46 FF FF 4 10 6D  CRC=6D
R=10 F2 36 55 0 8 0 D0 P=1 31 0 4B 46 FF FF 4 10 D8  CRC=D8
R=10 8A 14 55 0 8 0 92 P=1 34 0 4B 46 FF FF E 10 69  CRC=69
R=10 F2 36 55 0 8 0 D0 P=1 31 0 4B 46 FF FF 4 10 D8  CRC=D8
R=10 8A 14 55 0 8 0 92 P=1 35 0 4B 46 FF FF 3 10 A3  CRC=A3
R=10 F2 36 55 0 8 0 D0 P=1 31 0 4B 46 FF FF 4 10 D8  CRC=D8
R=10 8A 14 55 0 8 0 92 P=1 35 0 4B 46 FF FF 3 10 A3  CRC=A3
R=10 F2 36 55 0 8 0 D0 P=1 31 0 4B 46 FF FF 4 10 D8  CRC=D8
...and on and on and on...

Now, of course, I thought I might have a bad sensor, so I swapped out one sensor each time, while running only four, and it worked every time.  Every time I added a fifth sensor, it would loop.

I'm not running parasite power, and have the 4.7k pull-up (to +5V) resistor on the DQ line, which also goes to the Arduino.  Pin 1 is going to ground, and pin 3 is connected to the same +5v source.

Anyone have any ideas?
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