Acrosser AIV-HM76V1FL User Manual
Page 51
AIV-HM76V1FL Series User Manual
51
Syntax:
i32 getCanMask(struct CanMask *mask)
Description:
This function gets the current setting of the acceptance
masks. Masks are used to determine which bits in the
ID field of the CAN packet are examined with the filters.
There are two acceptance masks (mask0 and mask1)
and six acceptance filters (filter0 ~ filter5) in the CAN Bus
subsystem. Filter0 ~ filter1 are associated with mask0.
Filter2 ~ filter4 are associated with mask1.
Here is the Mask/Filter truth table:
Mask bit n
Filter bit n
Message ID
bit n
Accept or
reject bit n
0
x
x
Accept
1
0
0
Accept
1
0
1
Reject
1
1
0
Reject
1
1
1
Accept
Note: x = don’t care
Parameters:
This parameter ‘mask’ is a pointer to a variable of type
‘CanMask’. Users use the field ‘maskId’ to indicate the
mask they want and the API put the setting of the mask in
the ‘mask’ field.
struct CanMask {
u8 maskId; // 0 or 1
u32 mask;
}
Return Value:
If this function receives the mask setting successfully, it
returns 0, any other returned value stands for error.
For example:
struct CanMask a_mask;
a_mask.maskId = 0; // indicate the mask0
i32 result;
result = getCanMask(&a_mask); // The setting of the
mask is put at
// a_mask.mask
if( result != 0)
printf(“Fail to get mask!\n”);