I-87004W User Manual, v 1.0.1, Aug 2017 E-mail: [email protected]
Copyright © 2017 ICP DAS Co., Ltd. All Rights Reserved.
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Chapter 3. Using DS18B20
Temperature Sensor
The I-87004W provides four ports and up to 20 DS18B20 sensors
can be connected to each port. Each DS18B20 has a unique
64-bit serial code, which can be represented by 16 characters in
hexadecimal format. The user must know the serial code of each
DS18B20 sensor and assign unique channel index to each
DS18B20 when using the I-87004W to read temperature data from
DS18B20 sensors.
When the I-87004W is powered on, it scans all the DS18B20
sensors connected for each port. Each scanned DS18B20 is
checked to see whether a channel index is assigned. If it is not
assigned, then the DS18B20 is added to the not assigned list.
The user has to check the not assigned list and assign channel
index for all members in the not assigned list. This needs to be
done only once, since all of the data will be saved to the
non-volatile memory.
When a DS18B20 sensor is broken and is replaced by a new one,
its channel index should be removed first. Then, send command
to I-87004W to rescan DS18B20 on the port. The new DS18B20
will be found and put to the not assigned list. The user can
reassign the previous channel index to the new DS18B20.
