Elgas EDT 101, User Manual

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Delay stores copy of the Delay parameter passed by the Synchronize Datalogging command.
Period stores copy of the Period parameter passed by the Synchronize Datalogging command.
Number of samples gives the actual number of samples stored in the Data memory.
Data registers store temperature samples measured during datalogging. The registers are
being filled starting with register 40088 and continuing towards higher register numbers.
The oldest sample can be found in the register 40088, the most recent one in the register
Most recent sample register no. = 40088 + Number of samples - 1.
Each sample is represented as unsigned integer which can be converted to temperature in
physical units using formula given in paragraph 4.3.6.
4.3.8 Data types
A few different data types are used to represent various parameters stored in the transducer’s
memory:
uchar 8-bit unsigned value. Range from 0 to +255. The 8-bit value is stored in the Least
significant byte of the 16-bit register. The most significant byte of the 16-bit register is
ignored however it is recommended to write it always as 0x00.
int 16-bit signed value in 2’s complement format. Range from –32768 to +32767.
uint 16-bit unsigned value. Range from 0 to 65535.
ulong 32-bit unsigned value stored in two subsequent 16-bit registers. Higher order bits are
stored in register n, lower order bits in register n+1. Range from 0 to 4294967295.
float 32-bit single precision floating point value stored in two subsequent 16-bit registers.
Register n,
[EEEE EEEE SMMM MMMM]
– exponent (offset 129), sign and mantisa
Register n+1,
[MMMM MMMM MMMM MMMM]
– mantisa
examples: +100.25 is coded as 8748h, 8000h
-12.5 is coded as 84C8h, 0000h
+3.1415 is coded as 8249h, 0E56h