2. Acceptance Filter

Dual filter mode

This mode is not supported by this firmware.

Single filter mode

This mode is not supported by this firmware.

Simple filter mode

Mechanism

The received frames are filtered based only on its CAN ID and type of CAN ID.

The following table shows the relationship between filter code, mask and received CAN ID. The table corresponding to the type of CAN ID is applied.

11bit ID
Code	AC0 bit7	AC0 bit6-0	AC1	AC2 bit7-3	AC2 bit2-0	AC3
Mask	AM0 bit7	AM0 bit6-0	AM1	AM2 bit7-3	AM2 bit2-0	AM3
Rx frame	1	-	-	-	CAN ID bit10-8	CAN ID bit7-0

29bit ID
Code	AC0 bit7	AC0 bit6-5	AC0 bit4-0	AC1	AC2	AC3
Mask	AM0 bit7	AM0 bit6-5	AM0 bit4-0	AM1	AM2	AM3
Rx frame	0	-	CAN ID bit 28-24	CAN ID bit 23-16	CAN ID bit 15-8	CAN ID bit 7-0

Here '-' means the corresponding bit is not used for acceptance decision. The received frame is accepted if the following condition is satisfied for every bits.

(Code) & (~Mask) == (Rx frame) & (~Mask)

Examples

Example 1:

• Mode - W2[CR]
• Code - M00000000[CR]
• Mask - mFFFFFFFF[CR]

All bits are disabled by acceptance mask i.e. all frames are received. This is default when power on.

Example 2:

• Mode - W2[CR]
• Code - M80000100[CR]
• Mask - m00000000[CR]

The base CAN ID 0x100 is accepted and the other base CAN IDs are ignored. All extended CAN IDs are ignored.

Example 3:

• Mode - W2[CR]
• Code - M18DB0000[CR]
• Mask - m0000FFFF[CR]

All extended CAN IDs between 0x18DB0000 and 0x18DBFFFF are accepted. The other extended CAN IDs and all base CAN IDs are ignored.