Sys Tec Electronic USB-CANmodul - Page 63

Software
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SYS TEC electronic GmbH 2001 L-487e_6
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These bits correspond to:
a) Standard frame (11-bit identifier):
dwACR_p
31 30 ... 21 20 19 ... 16 15 14 ... 8 7 6 ... 0
⇓
dwAMR_p
31 30 ... 21 20 19 ... 16 15 14 ... 8 7 6 ... 0
⇓
CAN Identifier Data Byte 0 Data Byte 1
10 9 ... 0
R
T
R
free 7 6 ... 0 7 6 ... 0
b) Extended frame (29-bit identifier):
dwACR_p
31 30 ... 3 2 1 0
⇓
dwAMR_p
31 30 ... 3 2 1 0
⇓
CAN Identifier
28 27 ... 0
R
T
R
free
The macros USBCAN_SET_AMR (extended, can_id, rtr) and
USBCAN_SET_AMR (extended,can_id, rtr) can be used to calculate
the filter values. The parameter extended indicates if it is a 29-bit
message (TRUE) or a 11-bit message (FALSE). The parameter
can_id shows the filter value as CAN identifier. The parameter rtr can
be used to filter RTR frames. This parameter can be TRUE (=1) or
FALSE (=0).