Datasheet

Table Of Contents

Range Filter

The filter matches for all received frames with Message IDs in the range defined by SF1ID/SF2ID for

standard frames or EF1ID/EF2ID for extended frames.

There are two possibilities when range filtering is used together with extended frames:

EFT = “00” The Message ID of received frames is AND’ed with the Extended ID AND Mask (XIDAM)

before the

range filter is applied

EFT = “11” The Extended ID AND Mask (XIDAM) is not used for range filtering

Filter for specific IDs

A filter element can be configured to filter for one or two specific Message IDs. To filter for one specific

Message ID, the filter element has to be configured with SF1ID = SF2ID resp. EF1ID = EF2ID.

Classic Bit Mask Filter

Classic bit mask filtering is intended to filter groups of Message IDs by masking single bits of a received

Message ID. With classic bit mask filtering SF1ID/EF1ID is used as Message ID filter, while SF2ID/EF2ID

is used as filter mask.

A zero bit at the filter mask will mask out the corresponding bit position of the configured ID filter, e.g. the

value of the received Message ID at that bit position is not relevant for acceptance filtering. Only those

bits of the received Message ID where the corresponding mask bits are one are relevant for acceptance

filtering.

In case all mask bits are one, a match occurs only when the received Message ID and the Message ID

filter are identical. If all mask bits are zero, all Message IDs match.

Standard Message ID Filtering

The figure below shows the flow for standard Message ID (11-bit Identifier) filtering. The Standard

Message ID Filter element is described in 39.9.5 Standard Message ID Filter Element.

Controlled by the Global Filter Configuration GFC and the Standard ID Filter Configuration SIDFC

Message ID, Remote Transmission Request bit (RTR), and the Identifier Extension bit (IDE) of received

frames are compared against the list of configured filter elements.

SAM D5x/E5x Family Data Sheet

CAN - Control Area Network

Datasheet

DS60001507E-page 1215