2014-
02
34
Commands
1. A request is issued. The following parameters must be known here:
2. The identification system sends a response to the MODBUS master. If an error occurs, the
response contains an exception code. A write command must be executed from the first
address from the respective channel.
If an identification command is initiated several times (e.g., if you wish to execute a read
command several times in succession), the first four bytes of the identification telegram must
be modified accordingly. The toggle bit can be used for this.
Example:
In the following example, the tag type IPC03 is set to channel 2 and then a read command is
executed. The following prerequisites must be fulfilled:
■
One type IPH-XX read head is connected to channel 2.
■
The IP address is configured.
■
A network connection is established.
■
A MODBUS master is available (PC-based or PLC).
First step
The following parameter settings must be configured in the MODBUS master:
Start address (depending on channel)
Channel 0
0d
Channel 1
1000d
Channel 2
2000d
Channel 3
3000d
Channel 4
4000d
Number of registers to be written:
Maximum 123d
Table 7.5
Required request parameters
Slave IP address:
Identification system IP address
Timeout time:
1000 ms
Device ID:
1
Start address:
2000d
Number of registers to be written.
4d
Table 7.6
Required parameter settings on the MODBUS master
