Canmsg_T - Advantech PCI-1680U User Manual

4.4.1

canmsg_t

When users directly use ReadFile or WriteFile interface of Windows Native API to
call drivers, this structure is needed.
typedef struct {
int
int
ULONG
short int length;
UCHAR
} canmsg_t;
Member Description
Name
flags
cob
id
length
data
Remarks
8-bit flags are used to record types of messages during sending or receiving. The
meanings of these bits are:
Bit Declaration
0 MSG_RTR
1 MSG_OVR
2 MSG_EXT
3 MSG_SELF
4 MSG_PASSIVE
5 MSG_BUSOFF
6 Reserved
7 MSG_BOVR
ID shows type of CAN. When ID is 0xFFFFFFFF, it means error frame, which implies
that hardware overrun, error and busoff occur in drivers. Users can get the specific
type from flags.
If ID does not equal 0xFFFFFFFF, flags may be Remote frame, Extended frame,
Standard frame, Self Reception or software overrun.
flags;
cob;
id;
data[ 8 ];
Description
Types of messages.
Reserved.
ID of message.
of messages (0~8).
Data transferred (Made up of 0°´8 Byte data).
Meaning
RTR
Hardware OVER-
RUN
Extension
Self Reception
Error
BUSOFF
Reserved
Software OVERRUN 1 means receive buffer overrun of software.
49
Description
1 means Remote frame, 0 means data
frame.
1 means receive buffer overrun of hardware.
1 means Extended frame(29 bit identifier), 0
means Standard frame(11 bit identifier).
1 means self sending and receiving frame, 0
means receiving frame from other ports.
1 means bus error.
1 means busoff.
PCI-1680U/1682U User Manual