Simex SRD-99, User Manual

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User manual - DATA RECORDER SRD-99 and cooperating software
9.3. EXAMPLES OF QUERY/ANSWER FRAMES
The examples concern a unit with address 1. All values are given in the hexadecimal system.
Designations:
ADDR
Address of the device in the system
FUNC
Function number
REG H,L Higher and lower part of registry number, to which the command refers to
COUNT H,L Higher and lower part of registry counter number, to which the command refers
to, starting with the register, which is defined by REG (max. 32)
BYTE C Number of higher bytes in the frame
DATA H,L
Higher and lower part of data word
CRC L,H
Higher and lower part of CRC sum
1. Read of 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 00 7A 39 A7
DATA H,L - identification code (007Ah)
2. Change of the device address from 1 to 2 (write to reg. 20h)
ADDR FUNC REG H,L DATA H,L CRC L,H
01 06 00 20 00 02 09 C1
DATA H - 0
DATA L - new device address (2)
The answer (the same as the message):
ADDR FUNC REG H,L DATA H,L CRC L,H
01 06 00 20 00 02 09 C1
3. Read of the displayed value (measurement) for channel 1, the device address = 01h:
ADDR FUNC REG H,L COUNT H,L CRC L,H
01 03 00 01 00 01 D5 CA
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