VorTek SonoPro Professional S36 Series, Инструкция по эксплуатации

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Series S36 Instruction Manual Chapter 4 Serial Communications
800120 4-10
most significant bit set, and the data field will contain the
exception code byte, as follows:
If the first byte of a message is not equal to the unit’s Modbus
address, if the unit detects a parity error in any character in the
received message (with even or odd parity enabled), or if the
message CRC is incorrect, the unit will not respond.
Command Message Format
The start address is equal to the desired first register number minus
one. The addresses derived from the start address and the number
of registers must all be mapped to valid defined registers, or an
invalid data address exception will occur.
Normal Response Message Format
Exception Response Message Format
Examples
Read the exception status byte from the device with address 1:
01 07 41 E2
01 Device address
07 Function code, 07 = read exception status
41 E2 CRC
Exception
Code Description
01 Invalid function code — function code not supported by device
02 Invalid data address — address defined by the start address and number of registers
is out of range
03 Invalid data value — number of registers = 0 or >125 or incorrect data with the Write
Single Coil command