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