Need help with DS1822
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Hi,
I have been experimenting with a DS1822 thermometer. The distance from
the stamp to the DS1822 is about 50 feet, connected with 3 conductor
unshielded cable - about 24 gauge.
I had to reduce the pullup resistor on the DQ line to about 550 ohms
to get reliable readings. Is there any harm in running with such a
low value? Is there some minimum value for this resistor? Also, does
anyone have a routine to compute the CRC checksum for the DS1822?
Thanks,
Marylou
I have been experimenting with a DS1822 thermometer. The distance from
the stamp to the DS1822 is about 50 feet, connected with 3 conductor
unshielded cable - about 24 gauge.
I had to reduce the pullup resistor on the DQ line to about 550 ohms
to get reliable readings. Is there any harm in running with such a
low value? Is there some minimum value for this resistor? Also, does
anyone have a routine to compute the CRC checksum for the DS1822?
Thanks,
Marylou