DS1721 Datasheet, PDF (11/16 Pages) Dallas Semiconductor – 2-Wire Digital Thermometer and Thermostat

DS1721
Stop Convert T [22h]
This command stops temperature conversion. No further data is required. This command may be used to
halt a DS1721 in continuous conversion mode. After issuing this command, the current temperature
measurement will be completed, stored and the DS1721 will remain idle until a Start Convert T is issued
to resume conversions.
DS1721 COMMAND SET Table 4
2-WIRE BUS DATA
INSTRUCTION
DESCRIPTION
PROTOCOL AFTER ISSUING
PROTOCOL
REGISTER COMMANDS
Access
Configuration
Writes to/Reads from 8-bit
configuration/status register
ACh
1 data byte
Access TH
Writes to/Reads from
12-bit TH register
A1h
1 or 2 data bytes
Access TL
Writes to/Reads from
12-bit TL register
A2h
1 or 2 data bytes
CONVERSION COMMANDS
Start Convert T
Initiates temperature
conversion
51h
idle
Stop Convert T
Terminates continuous
conversions
22h
idle
Read
Temperature
Reads 12-bit
Temperature register
AAh
Read 1 or 2 data bytes
NOTES
1
1, 3
1, 3
2
2
3
NOTES:
1. Data direction depends upon R/ W bit in the 2-wire control byte.
2. In continuous conversion mode, a Stop Convert T command will halt continuous conversion. To
restart, the Start Convert T command must be issued. In one-shot mode, a Start Convert T command
must be issued for every temperature reading desired.
3. If the user only desires 8-bit thermometer readings, the master need only read 1 data byte and follow
with a NACK and STOP. If higher resolution is required, 2 bytes must be read.
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