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Section 5 Movement of Data Carriers and Command Status
RFID System
Operation Manual
Section 5
Communications
Read/Write Functions
■ Read/Write Command Processing
The read/write function is used for communications when the Data Carrier is motionless.
Therefore, always be sure that the Data Carrier is at the specified position, i.e., in the communications
area of the Read/Write Head. If the Data Carrier is missing, the ID Controller will return a response
with an error code of 72 (Data Carrier missing).
1. The host device confirms that a Data Carrier is at
the specified position and then sends a command
to the ID Controller.
2. The ID Controller performs write or read
processing according to the command.
3. After the processing has been completed, the
ID Controller returns a response to the host
device to indicate that the processing has
ended. The host device, upon receiving the
response, moves the workpiece (with the Data
Carrier) on the line.
Auto Read/Write Functions
■ Auto Command Processing
When the ID Controller has received an Auto Command, it does not send a response to the host
device until the Data Carrier approaches. The communications line between the Controller and the
host device will be busy until a Data Carrier approaches.
1. The host device sends an Auto Command to
the Read/Write Head.
2. The ID Controller does not respond to the host
device until the Data Carrier approaches, and
only at this time does the host device become
busy.
3. When a Data Carrier passes by the Read/Write
Head, data is read or written.
4. After processing has been completed, the ID
Controller returns a response to the host
device to indicating the end of processing.
Host device
READ or WRITE
command
Command completed
ID Controller Data Carrier
Not approaching
Data Carrier
Data Carrier
Stops
Stops
Moves
Response
Read or write
processing
Host device ID Controller Data Carrier
Auto Command
Busy
Command completed
Busy
Head 1
Head 1
Read or write
processing
Head 1
Head 1
Response
Head 1
processing
completed
Not approaching
Not approaching
Data Carrier
Passing