Data Tag Holding Registers; Value & Status Registers - Mantracourt T24-ACMi-SA User Manual

Data Tag Holding Registers

41100 - 41199 – 100 registers containing the unique data tags of the modules to be read from. Each data tag is a
2 byte HEX code unique to each transmitter module. The data tag registers can be written to individually and as a
block. These are the same data tags that can be configured via the T24-Toolkit
Value & Status Registers
41500 - 41799 – 300 registers containing the values from each transmitter module as well as the status and LQI
(Link Quality Indicator). The 4 Byte floating point values from each transmitter module are contained within two
consecutive registers followed by a single register containing the LQI and status of the same transmitter modules.
The data tag registers and value registers correspond such that the values and status from the data tag specified
in register 41100 are contained within 41500 to 41502 and the value and status for the data tag specified in
register 41199 are contained within registers 41797 to 41799.
41500
Item 1
Item 100
41797
When reading registers containing the floating point data the register pairs must be read at the same time
otherwise incorrect values could result because of partial updates during reading.
The two register presents a numeric value from n to n and consist of a 4 byte 32 bit float in IEEE 754 format.
MSByte
31 30 29 28 27 26 25
Exponent (8-bit )
Sign Bit
The byte containing the sign and exponent is sent first, with the LS byte of the mantissa being last.
The value of the number is thus
(-1)Sign * 2(Exponent-127) * 1.Mantissa
Note the 'assumed 1' before the mantissa. The exception to this is the special value 0.0, which is represented as 4
zeroes.
The precision of this format is to 7 digits.
eg. a floating-point number of -12345.678 is represented as – [hex] C640E6B6
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41100
Data Tag Register
Item 1
41199
Item 100
41501
Value Float
Value Float
41798
24 23 22 21 20 19 18
41502
Status Register
Status Register
41799
17 16 15 14 13 12 11
Fraction (23-bit)
261
LSByte
10 9 8 7 6 5 4 3
T24 Telemetry User Manual
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