Data Sheet
Datasheet SHT3x-DIS
www.sensirion.com May 2018- Version 5 13/22
Command
Hex Code
MSB
LSB
Heater Enable
0x30
6D
Heater Disabled
66
Table 16 Heater command (Clear blocks are controlled by
the microcontroller, grey blocks by the sensor).
4.11 Status Register
The status register contains information on the
operational status of the heater, the alert mode and on
the execution status of the last command and the last
write sequence. The command to read out the status
register is shown in Table 17 whereas a description of
the content can be found in Table 18.
Command
Hex code
Read Out of status register
0xF32D
Table 17 Command to read out the status register (Clear
blocks are controlled by the microcontroller, grey blocks by
the sensor).
Bit
Field description
Default
value
15
Alert pending status
'0': no pending alerts
'1': at least one pending alert
‘1’
14
Reserved
‘0’
13
Heater status
‘0’ : Heater OFF
‘1’ : Heater ON
‘0’
12
Reserved
‘0’
11
RH tracking alert
‘0’ : no alert
‘1’ . alert
‘0
10
T tracking alert
‘0’ : no alert
‘1’ . alert
‘0’
9:5
Reserved
‘xxxxx’
4
System reset detected
'0': no reset detected since last ‘clear
status register’ command
'1': reset detected (hard reset, soft reset
command or supply fail)
‘1’
3:2
Reserved
‘00’
1
Command status
'0': last command executed successfully
'1': last command not processed. It was
either invalid, failed the integrated
command checksum
‘0’
0
Write data checksum status
'0': checksum of last write transfer was
correct
'1': checksum of last write transfer failed
‘0’
Table 18 Description of the status register.
Clear Status Register
All flags (Bit 15, 11, 10, 4) in the status register can be
cleared (set to zero) by sending the command shown in
Table 19.
Command
Hex Code
Clear status register
0x 30 41
Table 19 Command to clear the status register (Clear
blocks are controlled by the microcontroller, grey blocks by
the sensor).
4.12 Checksum Calculation
The 8-bit CRC checksum transmitted after each data
word is generated by a CRC algorithm. Its properties are
displayed in Table 20. The CRC covers the contents of
the two previously transmitted data bytes. To calculate