Communications Settings; Communications Specifications - Omron EJ1 User Manual

Communications Settings

6-1

Communications Settings

6-1-1

Communications Specifications

142
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 EJ1 to the host computer and writing data from the host computer to
the EJ1.
The EJ1 uses different communications specifications from existing products
to improve communications operability.
1. Parameter Validity
The conditions for parameter validity that depended on the model and setting
status no longer apply.
2. Fixed Values for Setting Ranges
For example, the setting range for the target value is fixed to − 1,999 to 9,999,
regardless of the input type.
In other words, the setting ranges under the new specifications will not
change based on the input type or related parameters.
For parameters that set ranges with upper and lower limits, the specifications
now allow the upper and lower limits to be reversed.
Refer to 4-1-3 Analog Inputs, 4-3-4 Setting the Set Point, and MV Limiter on
page 74 in Section 4 Basic Units (TC4/TC2) before using the EJ1.
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 output
assignments when operations, such as selecting heating and cooling, are per-
formed.
Refer to 4-2-1 Control Output Assignments, Heating/Cooling Control on
page 67, and 4-3-4 Setting the Set Point in Section 4 Basic Units (TC4/TC2)
before using the EJ1.
Parameter name
Transmission path connection
Communications
Synchronization method
Transmission code
Error detection
Flow control
Retry function
• 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)
Settings
EDU (Port A/Port B)
Multipoint
RS-485
Start-stop synchronization
Binary/ASCII
BCC (Block Check Character)
None
None
Section 6-1