Rockwell Automation 56RF RFID System User Manual - Manual (Page 77)

Rockwell Automation Publication 56RF-UM001A-EN-P - October 2011 77
RSLogix 5000 Code Examples Chapter 9
Inventory The inventory command returns the UUID and DSFID information from the
RFID tags in the field. This command can read up to a maximum of four tags.
The more tags in the field, the more time the tags need to be in the field to
complete the inventory command. By setting the output image fields to specific
values, the Inventory command returns the following information:
1. Returns the number of tags in the field and the UUID of each tag. Set
Address =0, Length = 0 and Data[0] = 0
2. Returns the number of tags in the field, the UUID and the DSFID of each
tag. Set Address =0, Length = 1 and Data[0] = 0
3. Returns the number of tags in the field, the UUID and the DSFID of each
tag that meets the specified AFI. Set Address =1, Length = 1 and Data[0]
= AFI value. If the AFI value is 0, then all the tags are reported.
Set the following values in the output image table:
a. xx:O.Channel[0].Command = 20
b. xx:O.Channel[0].Address = 0 (or 1, see below)
c. xx:O.Channel[0].Block = 0
d. xx:O.Channel[0].Data[0] = 0 (or 1, see below)
e. xx:O.Channel[0].Length = 0 (or 1, see below)
f. xx:O.Channel[0].Reset = 0
g. xx:O.Channel[0].Timeout = 0
h. xx:O.Channel[0].UIDLow = 0
i. xx:O.Channel[0].UIDHi = 0
Notes:
1. Set Address = 0 to get all tags in the RF field.
2. Set Address = 1 to get all tags that have the AFI value specified in the
Data[0] location.
3. Set Length = 0 to get only the UUID for each tag.
4. Set Length = 1 to get both the UUID and the DSFID for each tag.
5. Set Data[0] = 0 to return all tags in the RF field.
6. Set Data[0] = AFI value (but not zero) to return only those tags that have
that AFI value