Helmholz 700-651-CAN01, Руководство пользователя

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5.5.2 29-bit protocol
Byte Content Transmit Object
0 Len + RTR
1 HighByte HighWord CAN identifier
2 LowByte HighWord CAN identifier
3 HighByte LowWord CAN identifier
4 LowByte LowWord CAN identifier
5 Data byte 1
6 Data byte 2
7 Data byte 3
8 Data byte 4
9 Data byte 5
10 Data byte 6
11 Data byte 7
12 Data byte 8
The entire CAN message header is stored in the first 5 bytes (0-4).
Byte 0
15 14 13 12 11 10 9 8
Data length RTR unused
Byte 1 Byte 2
15 14 8 12 11 10 9 8 7 6 5 4 3 2 1 0
unused High Word CAN identifier (13 bits)
Byte 3 Byte 4
15 14 8 12 11 10 9 8 7 6 5 4 3 2 1 0
Low Word CAN identifier (16 bits)
Transmission of the message is initiated by inverting bit 0 in byte
0 of the
HANDSHK_OUT area.
The Transmit Object can be transmitted via the device parameters
of the DP/CAN coupler cyclically by means of a timer.
Cyclic transmission via the timer is triggered by inverting the bit
0 in byte 0 of the
HANDSHK_OUT area.
A change of transmit data is activated on cyclic transmission only
by inversion of bit 0 in byte 0 of the
HANDSHK_OUT area.
5.6 PLC diagnostics
SFC 13 – “DPNRM_DG” can be used to fetch the diagnostic data
from a DP slave.
Parameter Direction Type Example
REQ IN BOOL TRUE
LADDR IN WORD W#16#3FE
RET_VAL OUT INT ; MW 100
RECORD OUT ANY P#DB13.DBX0.0 byte 10
BUSY OUT BOOL M 7.0
DP/CAN Coupler 25