Datasheet

DS1621
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Table 3. DS1621 COMMAND SET
INSTRUCTION DESCRIPTION PROTOCOL
2-WIRE BUS DATA
AFTER ISSUING
PROTOCOL NOTES
TEMPERATURE CONVERSION COMMANDS
Read Temperature Read last converted temperature
value from temperature register.
AAh <read 2 bytes data>
Read Counter Reads value of Count_Remain A8h <read data>
Read Slope Reads value of the
Count_Per_C
A9h <read data>
Start Convert T Initiates temperature
conversion.
EEh idle 1
Stop Convert T Halts temperature conversion. 22h idle 1
THERMOSTAT COMMANDS
Access TH Reads or writes high
temperature limit value into TH
register.
A1h <write data> 2
Access TL Reads or writes low
temperature limit value into TL
register.
A2h <write data> 2
Access Config Reads or writes configuration
data to configuration register.
ACh <write data> 2
NOTES:
1. 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.
2. Writing to the E
2
requires a maximum of 10ms at room temperature. After issuing a write command,
no further writes should be requested for at least 10ms.