Simex STI-73, Руководство пользователя

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User manual - RATEMETER STI-73
10.3. EXAMPLES OF QUERY/ANSWER FRAMES
Examples apply for device with address 1. All values are represent hexadecimal.
Field description:
ADDR
Device address on modbus network
FUNC Function code
REG H,L Starting address (address of first register to read/write, Hi and Lo byte)
COUNT H,L No. of registers to read/write (Hi and Lo byte)
BYTE C
Data byte count in answer frame
DATA H,L
Data byte (Hi and Lo byte)
CRC L,H
CRC error check (Hi and Lo byte)
1. Read of the displayed value (measurement) and status, the device address = 01h:
ADDR FUNC REG H,L COUNT H,L CRC L,H
01 03 00 01 00 03 54 0B
The answer :
ADDR FUNC BYTE C DATA H1,L1 DATA H2, L2 DATA H3.L3 CRC L,H
01 03 06 00 01 86 A0 00 00 2A B4
DATA H1, L1 - reg. 01h (1 - high word of measurement value)
DATA H2, L2 - reg. 02h (86A0h - low word of measurement value ),
DATA H3, L3 - reg. 03h (0 - measurement status).
In this example measurement value is equal 186A0h (100 000 in decimal format).
Decimal point position is not included in measurement value (reg. 01h and 02h).
Decimal point position can be read from reg. 04h (
“ PrEc ” parameter).
2. Read of device ID code
ADDR FUNC REG H,L COUNT H,L CRC L,H
01 03 00 21 00 01 D4 00
The answer:
ADDR FUNC BYTE C DATA H,L CRC L,H
01 03 02 20 66 21 AE
DATA - identification code (2066h)
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