Omron C200HW-CORT21 Operation Manual page 47

Receiving a user defined CAN message
Identifier filter
Example
PLC start address
Note
Max. 15 messages buffered
Word n to word n+2 indicate which identifiers the C200HW-CORT21 must be
able to receive. Word n and word n+1 indicate the identifier range. To be able
to narrow down the number of identifiers within this range, word n+2
indicates which bits in word n must be matched and which are don't cares.
bit value '0' = don't care
bit value '1' = must match
The use of word n to word n+2 is explained with a few examples.
1. Configuring C200HW-CORT21 to receive one specific identifier, e.g.
0200h.
Set the minimum and maximum identifier to the same value and set
the identifier mask to 'all bits must match':
word n = 0200, word n+1 = 0200, word n+2 = 07FF
2. Configuring C200HW-CORT21 to receive a range of identifiers, e.g.
010Ah to 0114h.
Set the minimum and maximum identifier value to cover the range
and set the identifier mask to 'all bits don't care':
word n = 010A, word n+1 = 0114, word n+2 = 0000
3. Configuring C200HW-CORT21 to receive specific identifiers within a
range, e.g. receive all odd identifiers within the range 010Ah to 0114h.
Set the minimum identifier to the first odd identifier in the range and
the maximum identifier to the maximum value and the identifier mask
to match the first bit:
word n = 010B, word n+1 = 0114, word n+2 = 0001
Note The C200HW-CORT21 ignores bits 11 to 15 of word n ~ word n+2 of the
IOWR message structure. Also, the Unit does not check the validity of word n
~ word n+2 e.g. when the identifier value of word n is greater than word n+1,
no messages will be received.
Word n+3 in the IOWR message structure indicates the start address of the
PLC memory area to where the received CAN messages must be transferred
during the I/O refresh. The table below shows the definition of the PLC start
address.
PLC start address
0000 ~ 5900
Word n+2
A000 ~ A140
A300 ~ A420
When an incorrect PLC start address is indicated, error code 0404 is added
to the error log and received messages are no longer transferred to the PLC.
The received message(s) are first stored in a buffer. Up to 15 messages can
be stored. The last received message is always stored at the top of the buffer
and if there are already 15 messages stored, the oldest message is shifted
out of the buffer.
DM0000 ~ DM5900
IR000 ~ IR140
IR300 ~ IR420
Section 4-6
(C200HE: 0000 ~ 4000)
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