User`s manual

Western Reserve Controls, Inc. 1782-JDC User’s Manual
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baud rate to autobaud, you must do it via the parameter object. The definition is included in
the EDS file for easy configuration. Just use your configuration tool to access the device
parameters. The baud rate is parameter 7. Select the proper baud rate and upload the
parameter to the device. If your configuration tool does not support EDS parameter
configuration, you will have to perform the operation manually. To do this, set the parameter
Class 15 (F
hex
), instance 7, attribute 1 to the value in Table 2-1.
NOTE: If you change the baud rate, the new baud rate will not become effective until the
unit is power cycled or a reset command is received by the Identity Object (Class 1,
Instance 0, reset).
Table 2-1 Baud Rate Selection
Baud Rate
Value
Baud
Rate
0 125k
1 250k
2 500k
3 Autobaud
2.4 How to Install a Serial Network
1. The communication between your serial device(s) and the 1782-JDC is a RS232 3-wire,
RS485 2-wire or 5-wire RS422/485 differential network. Connect an appropriate cable to
your device.
2. Connect the other end of the cable to the JDC using the 3-point or 5-point terminal plug
provided. Note the terminal markings on the JDC case. See Figure 4-1.
3. Turn on power to the serial device and the JDC.
4. Set up the ASCII buffer sizes on the JDC. (The defaults are 20 and 20). If more than 20
bytes are required for the transmit or receive buffers, set parameters 5 and 6 in your
configuration file to the buffer size you need for your ASCII data (NOTE: this will modify
the IO message size. You will need to reconfigure the poll / COS / cyclic transmit and
receive data sizes if you modify the ASCII buffer size from the default value. In many
configuration tools, this will unmap the data in your scanner’s scan table. They must be
remapped in order to be able to process the data in your PLC or software) These
parameters can be reached in the Parameter Class 15 (F
hex
), Instances 5 and 6, Attribute
1 if you need to configure these manually (See Table A-10).
2.5 How to Read Serial Device Input Data from the JDC
1. Set up the receive size of your connection to equal the (Max Number of Receive Chars
+ 3) in your Master’s scan table. The default value should be 23 (20+3).
2. Map the data from your IO response to your scanners memory map. The device’s
response is byte aligned. The first byte indicates the receive record of the data. The
second byte contains the JDC's serial status indicator (00 is normal). The third byte
contains the length of the message being transmitted by the JDC. The subsequent bytes
contain the serial buffer data from the serial input until and including the latest received