DS1629
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COMMAND SET
The DS1629 command set is shown below.
Access Config [ACh]
If R/
is 0, this command writes to the configuration register. After issuing this command, the next data
byte value is to be written into the configuration register. If R/
is 1, the next data byte read is the value
stored in the configuration register. Because the MSB of the configuration register is read/write and the
LSB is read-only, the user only needs to write one byte to the register. One or two bytes can be read.
Start Convert T [EEh]
This command begins a temperature conversion. No further data is required. In one-shot mode, the
temperature conversion will be performed and then the DS1629 will remain idle. In continuous mode, this
command will initiate continuous conversions. Issuance of this protocol may not be required upon
DS1629 power-up, depending upon the state of the CNV bit in the configuration register.
Stop Convert T [22h]
This command stops temperature conversion. No further data is required. This command may be used to
halt a DS1629 in continuous conversion mode. After issuing this command, the current temperature
measurement will be completed, and then the DS1629 will remain idle until a Start Convert T is issued to
resume conversions.
Read Temperature [AAh]
This command reads the last temperature conversion result from the Thermometer Register in the format
described   in   the   OperationMeasuring   Temperature   section.   If   ones   application   can   accept
thermometer resolution of only 1.0癈, the master only must read the first data byte and follow with a
NACK and STOP. For higher resolution, both bytes must be read.
Read Counter [A8h]
This command returns the 8-bit COUNT_REMAIN value, used for high resolution thermometer
calculations.
Read Slope [A9h]
This command returns the 8-bit COUNT_PER_C value, used for high resolution thermometer
calculations.
Access Clock [C0h]
Accesses the DS1629 clock/calendar register. If R/
is 0, the master will write to the clock register (set
the clock). If R/
is 1, the clock register is read. The clock register is addressed, so the user must
provide a beginning byte address, whether a read or write is performed. A write to or read from this
register or the clock alarm register is required to clear the clock alarm flag (CAF). See Figure 6 for the
protocol and Figure 2 for the clock register map.
Access Clock Alarm [C7h]
Accesses the DS1629 clock alarm register. If R/
is 0, the master will write to the clock alarm register
(set/ change the alarm). If R/
is 1, the clock alarm register is read. The clock alarm register is
addressed, so the user must provide a beginning byte address, whether a read or write is performed. A