Vaisala HMM105 - Manual (Page 21)

Chapter 2 _______________________________________________________________ I2C Interface
VAISALA ____________________________________________________________________ 19
Data Registers
The register table describes all available parameters and their properties.
The properties are: parameter meaning, ID, name, data type, length and
persistence. Persistence defines if the parameter is saved in EEPROM
(non-volatile memory) or in RAM. Make sure not to write excessively to
the EEPROM, as it has a maximum lifetime of approximately 30000
cycles.
Data Formats
Table 31 Data Formats
Data type name Size (Bytes) Other
Byte 1 Value range 0...255
Integer 2 Value range -32768...32767
Unsigned integer 2 Value range 0…65535
Long integer 4 Value range
−2,147,483,648…2,147,483,647
Unsigned long integer 4 Value range 0…4,294,967,295
Float 4 According to IEEE-754. NaN
(7FC00000) is returned if no value
is available
String Max. 50 All characters accepted
(00h…FFh)
NOTE Maximum string size refers to maximum communication buffer size.
Actual reserved storage space for each parameter can be seen in Table 32
on page 20
NOTE Integers and floating point numbers are sent LSB first.