Chino KR2S, Инструкция по эксплуатации

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INST.No.INE-863B KR2S
【
Communication Interface
】
Instruction Manual
-21-
7-1 Transmission mode of message
There are 2 types of the RTU (Remote Terminal Unit) mode and the ASCII mode.
(Table 1. Comparison of RTU mode and ASCII mode)
Item RTU mode ASCII mode
Transmission code Binary ASCII
Error detection
(Error check)
Vertical direction Parity
Horizontal direction CRC-16 LRC
Character
configuration
Start bit 1 bit
Data bit 8 bits 7 bits, 8 bits
Parity bit
None, odd, even
None*, odd, even
Stop bit 1bit/2 bits
Message start code None : (Colon)
Message end code None CR, LF
Data time interval Less than 28-bit hours Less than 1 second
* When the data bit is 7 bits, [Parity bit None] is not applicable.
7-1-1
Transmission data
The RTU mode is binary transmission. The ASCII mode divides 8 bits binary of the RTU into higher 4
bits and lower 4 bits and converts into characters respectively (0-9, A-F).
Ex) RTU mode ASCII mode
67H
36H (
“6”)
89H 37H (
“7”)
ABH 38H (
“8”)
39H (
“9”)
41H (
“A”)
42H (
“B”)
The RTU mode is half in the message length as compared to the ASCII mode and enables the
efficient transmission.
7-1-2
Message frame configuration
The RTU mode is configured by message parts only.
The ASCII mode is configured by the start character “: (colon, 3AH)”, messages and the end character “CR
(carriage return, ODH) + LF (Line feed, OAH)”.
RTU mode ASCII mode
Message : Message CR LF
As the ASCII mode has the start character of “:” it has an advantage that the troubleshooting is easy.