Omron C200HW-CORT21, Руководство по эксплуатации

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Receiving a user defined CAN message
Section 4-6
44
Note The C200HW-CORT21 ignores bits 11 to 15 of word n.
If no other node is connected to the network or the CAN interface of the Unit
is in error, the C200HW-CORT21 will not be able to transmit the message. In
that case error code 0448 is added to the error log for each message that the
Unit is unable to transmit.
Example The following example shows how two bytes are transmitted with identifier 0.
In this example, the Machine number is set to ‘1’.
13.00
IOWR (-)
TX_data #0003
DM0400
#1003
255.06 12.00
EQ_FLAG ERROR
PLC memory address Contents
DM0400 0000
DM0401 0002
DM0402 0201
4-6 Receiving a user defined CAN message
Control code #0004
The C200HW-CORT21 enables to receive an arbitrary CAN message with a
combination of the IOWR instruction and the I/O refresh.
The frame of a CAN message is shown in the picture below.
* Identifier (11 bits) * Data length (DLC) Data byte 1 Data byte 8 *
* Frame control bits, not important for this function
The IOWR instruction is used to indicate to the Unit which identifier(s) to
receive and to which PLC area the received message must be transferred.
The figure below shows the IOWR message structure.
IOWR message structure word n Minimum identifier [hex] range: 0000h ~ 07FFh
word n+1 Maximum identifier [hex] range: 0000h ~ 07FFh
word n+2 Identifier mask [hex] range: 0000h ~ 07FFh
word n+3 PLC start address