Allen-Bradley 56RF, Руководство пользователя

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80 Rockwell Automation Publication 56RF-UM001A-EN-P - October 2011
Chapter 9 RSLogix 5000 Code Examples
In example 3, we get the tag information for only those tags the have a specific
AFI. In this example the AFI is 57. Address = 1, Length = 1 and Data[0] = 57.
Two of the four RFID tags that were present in the RF field at the time the read
command was executed had AFI set to 57. The controller tag values are shown
below. The data shows the number of tags in the RF field, the DSFID and the
UUID for each of these tags.
Lock AFI The Lock AFI command will lock the one byte of information for the
Application Family Identifier (AFI), preventing it from being modified in the
future.
Once the AFI byte is locked, it cannot be unlocked.
The AFI is used to group RFID tags by application. This allows the transceiver to
send out an AFI and target only the tags that meet the application criteria.
Set the following values in the output image table:
a. xx:O.Channel[0].Command = 42
b. xx:O.Channel[0].Address = 0
c. xx:O.Channel[0].BlockSize = 0
d. xx:O.Channel[0].Data[0] = 0
e. xx:O.Channel[0].Length = 0
f. xx:O.Channel[0].Reset = 0
g. xx:O.Channel[0].Timeout = 0
h. xx:O.Channel[0].UIDLow = UIDLow
i. xx:O.Channel[0].UIDHi = UIDHi
The UIDLow and UIDHi bytes must be specified to lock the AFI value. The
UUID can be found by performing the Inventory command.