Omron EJ1G, User Manual

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Communications Settings
Section 6-1
6-1 Communications Settings
Communications are programmed on the host computer. Descriptions of com-
munications in this manual are therefore written from the viewpoint of the host
computer. For example, references to reading and writing mean reading data
from the EJ1G to the host computer and writing data from the host computer
to the EJ1G.
The EJ1G uses different communications specifications from existing prod-
ucts to improve communications operability.
1. Parameter Validity
The conditions for parameter validity that depended on the model and set-
ting status no longer apply.
2. Fixed Values for Setting Ranges
The SP will not change even if the SP Limiter is changed.
For parameters that set ranges with upper and lower limits, the specifica-
tions now allow the upper and lower limits to be reversed.
Refer to 5-3-3 Setting the Set Point, and MV Limiter on page 75 in Section
4 Basic Units (TC4/TC2) before using the EJ1G.
3. Automatic Offsetting of Setting Values
Accompanying changes outlined under Set Values for Setting Ranges,
above, there are no longer any restrictions in operations for the target value
limiter or target values for changes in the input type.
Under the new specifications, there is also no need to change control out-
put assignments when operations, such as selecting heating and cooling,
are performed.
Refer to 5-3-3 Setting the Set Point in Section 4 Basic Units (TC4/TC2) be-
fore using the EJ1G.
6-1-1 Communications Specifications
• The following communications settings are used.
• EDU (Port A)
The following settings are fixed.
- Baud rate: 38.4 kbps
- Communications data length: 7 (bit)
- Communications stop bits: 2 (bit)
- Parity: Even (bit)
Parameter name Settings
EDU (Port A/Port B)
Transmission Path Connection Multipoint
Communications RS-485
Synchronization Method Start-stop synchronization
Transmission Code Binary/ASCII
Error Detection BCC (Block Check Character)
Flow Control None
Retry Function None