KEYENCE N-410 - Manual (Page 127)

7-11
7-2 Device Assignments
PLC
Link
7
 Real time control
• Write either 0000 or 0001 to this area.
• This will be 0001 when the code reader is reading the code or the N-410 is writing to the PLC.
• This returns to 0000 after data has been written so that new data can be written in the +04 to +133
addresses.
In other words, if the +02 address contains 0000, the data is valid.
(Example 1)
The +02 address is normally 0000.
This becomes 0001 while data is being written, so when it become 0000 (at startup), the +04
to +133 addresses should be handled by program.
(Example 2)
The +02 address is normally 0001.
The +00 address becomes 0000 when data ends, so the +04 to +133 addresses should be
handled by program.
After this is handled, be sure to reset the +02 address to 0001. This allows the +02 address to act as
a trigger for new writing new data when it is set to 0000.
If codes are read consecutively, "real time processing" may allow data in the PLC to be
overwritten before it is processed. If this is the case, use of "sequence processing is
recommended".
 Sequence processing
• Write either 0002 or 0003 to this area.
• If the +02 address is 0002, new data can be written.
• This changes to 0003 after data has been written so that new data can be written in the +04 to +133
addresses.
• After program processing, set this back to 0002.0002If this is not set back to 0002, new data will not
be written.
• Data that cannot be sent will be stored in the N-410 send buffer. Refer to "Send Buffer Capacity"
(Page 4-9) for more information on N-410 buffer capacity.
• If the capacity of the buffer is exceeded, a buffer overflow will occur and "OVER" will be written.
This is used as the trigger input signal when reading codes.
This can be enabled or disabled in "Trigger area input" of the AutoID Navigator. If this is set to
"Disable", the area is released to the user.
Do not use this area if a sensor or other device is being used as the trigger input for a code
reader.
This area should be written to as follows.
• Begin reading (Trigger on): 0001
• End reading (Trigger off): 0000
Write 0000 to this area when not reading codes.
Note
+03
Read trigger area