SIMATIC RF382R Scanmode
J31069-D0214-U001-A4-7618, 10/2013
9
Note
Documenting parameter changes
A change in the communication-relevant parameters "baud rate" and "parity" must be well documented, because with
unknown interface parameterization, the reader cannot be addressed and can also no longer receive user data.
If the interface setting in the reader is no longer known, the host must search for the setting: e.g. telegram "Read status" -
wait for a reply. (Test variants with five baud rates and three parity settings)
Note
No reader communication after interface physics parameter is changed
An unintentional change in the interface physics parameter has the result that no further communication is possible with the
reader.
The RF310R Scanmode reader requires an adapter to convert RS-422 to RS-232.
Telegram structure
A telegram from the host to the reader is structured as follows:
Command Status
Quantity x 1st byte
2nd byte
...
x ... 1st byte xth byte
BCC
The acknowledgement from the reader to the host is structured as follows:
Command Error code
BCC
The acknowledgement is sent by the reader after it has finished performing the command.
Frame transmission
Properties of frame transmission:
●
The information about the version is appended to the parameters when reading.
●
The calculation of the BCC checksum is performed simply by XORing all bytes.
●
If there is a change in an interface parameter (baud rate, parity), an acknowledgment with the old setting is sent.
Following this, the new setting takes effect (scan data, next frame).
"Change parameters" telegram
All parameters can be changed, including those for the serial interface. Note the following:
●
The acknowledgement from the reader is sent with the old settings
●
The following scan data are sent with the new settings
The parameters can be stored in the reader either retentively or non-retentively:
●
In retentive parameterization, the transferred data are still available after the reader is restarted.
●
In non-retentive parameterization, the data are only changed for current operation. A restart will then occur with the old
parameters.
After the parameters are accepted and the acknowledgement is sent, the reader returns automatically to scan mode.
"Change parameters" telegram:
Command Status
Quantity
1st byte
2nd byte
...
20th byte
21st byte
BCC
0x01
0x00
21
Para
Para
...
Para
Para
"Change parameters retentively" telegram:
Command Status
Quantity
1st byte
2nd byte
...
20th byte
21st byte
BCC
0x01
0x01
21
Para
Para
...
Para
Para
