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52 - Configuring Read/Write Raw/ASCII Devices
DeviceMaster UP Modbus/TCP Quick Start: 2000477 Rev. G
Configuring Read/Write Raw/ASCII Devices
•
Dual Master – Read mode, go to Step
on Page 56 for configuration procedures.
9.
PLC Master/DeviceMaster UP Slave Mode Only:
Use the following procedure to configure PLC Master/DeviceMaster UP Slave mode.
a.
Set Rx (To PLC) Transfer Mode to Slave (PLC Polls).
b.
Set Tx (From PLC) Transfer Mode to Slave (PLC Writes).
c.
Set the Maximum Rx Data Packet Size to that of the largest expected receive data packet. This can be a
maximum of 246 bytes in Slave Rx mode.
d.
Set the Oversized Rx Packet Handling to either Truncate or Drop, depending how you want to handle
oversized received packets.
e.
Set Rx MS Byte First if you want to receive data most significant byte first.
f.
Set Tx MS Byte First if you want to transmit data most significant byte first.
g.
Set the Disable Non-Filtered To PLC Rx Queue option if you only want to receive the last received data
packet. (If two or more packets are received between received data requests, only the last received
data packet will be returned.)
h. Set the Disable Tx Sequence Number Check option if you want to disable the transmit sequence number
checking.
•
If selected, the transmit sequence number checking is disabled. All transmit messages will be
transmitted if the sequence number has been incremented or not.
•
If not selected, the sequence number is checked and the message will only be transmitted if the
sequence number has been updated.
Note: Go to Step
on Page 57 to complete configuration.
Note: You can use the Dual Master - Read method only if your PLC can
operate as a Modbus master and slave, simultaneously.