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All Rights Reserved. Copyright © 2000, Yokogawa Electric Corporation
TI 04L01A01-02E
4.4
Serial Communications (/C2,/C3)
By using serial communications, the DX100/200 can be controlled and configured from a host computer,
and data can be transferred to the host. In addition, the MODBUS communication protocol can be
selected.
4.4.1
RS-232(/C2)
Electrical and mechanical specifications
: Conforms to EIA RS-232-C (9 pins)
Connection format
: point to point
Communication format
: full duplex
Synchronization method
: start-stop asynchronous transmission
Control format
: Select from CS-RS, Xon/Xoff, Xon-RS,and None
Data length
: 7,8 [bit]
Baud rate
: Select from 1200, 2400, 4800, 9600, 19200, 38400 [bps]
Start bit
: 1 [bit]
Stop bit
: 1 [bit]
Parity
: Select from ODD, EVEN, and NONE
Communication data format
: Measured data : Select ASCII or binary
Configuration and control: ASCII
4.4.2
RS-422-A/485(/C3)
Electrical and mechanical specifications
: Conforms to EIA RS-422-A
Connection format
: Multidrop (1:N(N=1 to 32))
Communication format
: Four-wire half duplex
Synchronization method
: start-stop asynchronous transmission
Control format
: None
Data length
: 7,8 [bit]
Baud rate
: Select from 1200, 2400, 4800, 9600, 19200, 38400 [bps]
Start bit
: 1 [bit]
Stop bit
: 1 [bit]
Parity
: Select from ODD, EVEN, and NONE
Communication distance
: 1.2 km maximum
Communication data format
: Measured data : Select ASCII or binary
Configuration and control: ASCII
4.4.3
MODBUS Protocol
Basic specifications
Transmission medium : RS-232 or RS-422-A/485
Control format
: None
Baud rate
: Select from 1200, 2400, 4800, 9600, 19200, 38400 [bps]
Start bit
: 1 [bit]
Stop bit
: 1 [bit]
Parity bit
: Select from Odd, Even, and None
Transfer mode
: RTU (Remote Terminal Unit) mode
Data length
: 8 [bit]
Data interval
: 24 [bit time] or less
The end of the message is determined by a blank time period of 3.5 characters
or more.
Error detection
: Uses CRC-16