Delta OHM HD45 17A, Manual

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Example:
You may want to read the relative humidity measurement of a transmitter whose
current measure is 65.8%.
From Table 8.D we obtain that the relative humidity value is stored in register number
0003. In order to read the quantity value, you need to include in the request:
• address (= number - 1) of register with the first parameter (0002 = 0002h)
• number of parameters to be read (1 = 0001h).
Consequently, the command assumes the following format:
Command
Value Length Description
Function: 04h 1 byte Measurements reading command
Data: 00h First quantity address (MSB)
02h
2 bytes
First quantity address (LSB)
00h Number of quantities to be read (MSB)
01h
2 bytes
Number of quantities to be read (LSB)
The instrument will answer with the measured value: 65.8% x 10 = 658 = 0292h
Response
Value Length Description
Function: 04h 1 byte Measurements reading command
Data: 02h 1 byte Number of bytes for the values
02h Measured RH% value (MSB)
92h
2 bytes
Measured RH% value (LSB)