Control With Mv Commands Via Fb 45 Or Ident Profile; Status Displays Of The Mv Reader - Siemens SIMATIC MV440 Operating Instructions Manual

10.3.3

Control with MV commands via FB 45 or Ident profile

The reader is controlled by the MOBY commands "WRITE" and "READ" or by the Ident
profile commands "PHYSICAL-WRITE" and "PHYSICAL-READ". Chaining of commands is
not supported.
An RFID system typically has a linear memory area for each RFID tag from which data can
be read or to which data can be written. With a reader, the address space (in this case,
purely virtual) is used to map certain MV commands (Machine Vision commands). In addition
to this, the data "written", for example, to a certain address has a defined semantic meaning.
This chapter explains which address can be written to and which address can be read from
to achieve a certain response from the reader. The semantic meaning of the read data or
data to be written is also explained.
10.3.3.1

Status displays of the MV reader

Note
Startup of the code reader with FB 45 or Ident profile
You need to ensure the following after power "ON" when using FB 45 or the Ident profile
(with or without communication module) for the startup of the the code reader:
1. Set a startup flag in OB100 of the controller.
2. If the startup flag is set, you need to repeat the initialization ("init_run" or "INIT" command)
until positive acknowledgment is received.
3. Then, check the status bits (IN_OP, RDY) to verify the preconditions for further
commands.
4. To generate an error in the automation system, additionally monitor the maximum wait
time for positive acknowledgment of the initialization and expected status bit values.
The status bits IN_OP (in operation) and RDY (ready) of the reader indicate whether or not
the device has a group error or is in processing mode or STOP mode.
Depending on the status of the reader, various MV commands are permitted (see chapter
Preconditions for the commands (Page 265)) or an acknowledgement of the error (see
Group errors (Page 267)) required before the next MV command can be sent.
If the IN_OP bit is not set, there is a group error that must be acknowledged before
continued operation is possible. The acknowledgement mechanism via the interface module
is explained in chapter WRITE commands/MV command interface (Page 248).
The status display is only valid after initialization has been successfully performed ("MOBY
Param".init_run bit in FB45 or "instance DB-RFID standard profile".INIT bit with the Ident
profile).
In addition to the error output bytes of FB45 or of the Ident profile block, these bits must
always be queried before an MV command is sent.
SIMATIC MV420 / SIMATIC MV440
Operating Instructions, 04/2013, A5E02371045-06
Process interfacing via an automation system (PLC, PC)
10.3 Control with FB 45 and Ident profile
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