KEYENCE N-410 User Manual
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7-6
PLC
7
7-2
Device Assignments
Details of DM assignments
This section explains assignments to each address.
This area contains notifications of buffer overflows on connected BL Series barcode readers.
It normally contains "0000", but will be changed to "0001" if an overflow has occurred.
It will return to "0000" when the code reader's buffer has been cleared.
This area is used to clear buffers. This area should be written to with binary data.
"0000" should be written in the +01 address at most times. To clear the BL Series buffer when
"0001" is written to the +00 address, write "0001" to that address.
When the +00 address has changed to "0000", write "0000" to the +01 address.
If the +01 address is left as "0001", no notice will be given the next time a buffer overflow
occurs.
When "0001" is not written to the +00 address, once the buffer has been cleared,
Make sure to use a program to write "0000".
This area specifies the write header of read data. This area should be written to with binary data.
Set a different value for each ID number. Overlapping addresses will not cause an error.
However, if code readers with different ID numbers read consecutively, the first set of data will be
overwritten.
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.
This area is used as a flag indicating whether code data has been read.
This is intended to be used in one of the two methods that follow.
+00
BL Series buffer overflow notification
+01
Buffer overflow clear
+02 to 32
Data write header address for each ID no.
+33 to 63
Read trigger area for each ID no.
A+00 (A is the data write header address specified in +02 to +32)
Data write flag area
Note