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5 frame filtering, Section 7.2.3.5, Section 7.2.3.5 “frame filtering – Rainbow Electronics AT86RF231 User Manual

Page 61: Section 7.2.3.5 “frame filtering” on, Is also

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61

8111A–AVR–05/08

AT86RF231

7.2.3.5

Frame Filtering

Frame Filtering is an evaluation whether or not a received frame is dedicated for this node. To
accept a received frame and to generate an address match interrupt IRQ_5 (AMI) a filtering pro-
cedure as described in IEEE 802.15.4-2006, section 7.5.6.2 (Third level of filtering) is applied to
the frame. The AT86RF231 RX_AACK mode accepts only frames that satisfy all of the following
requirements (quote from IEEE 802.15.4-2006, section 7.5.6.2):

Address match, indicated by interrupt IRQ_5 (AMI), is further controlled by the content of sub-
fields of the frame control field of a received frame according to the following rule:

If (Destination Addressing Mode = 0 OR 1) AND (Source Addressing Mode = 0) no IRQ_5 (AMI)
is generated, refer to

Section 8.1.2.2 “Frame Control Field (FCF)” on page 80

. This effectively

causes all acknowledgement frames not to be announced, which otherwise always pass the fil-
ter, regardless of whether they are intended for this device or not.

For backward compatibility to IEEE 802.15.4-2003 third level filter rule 2 (Frame Version) can be
disabled by register bits AACK_FVN_MODE (register 0x2E, CSMA_SEED_1).

Frame filtering is available in Extended and Basic Operating Mode, refer to

Section 7.1 “Basic

Operating Mode” on page 33

, a frame passing the frame filtering generates an IRQ_5 (AMI), if

enabled.

Notes

• Filter rule 1 is affected by register bits AACK_FLTR_RES_FT and AACK_UPLD_RES_FT,

Section 7.2.7 “Register Description - Control Registers” on page 68

.

• Filter rule 2 is affected by register bits AACK_FVN_MODE,

Section 7.2.7 “Register

Description - Control Registers” on page 68

.

1.

The Frame Type subfield shall not contain a reserved frame type.

2.

The Frame Version subfield shall not contain a reserved value.

3.

If a destination PAN identifier is included in the frame, it shall match macPANId or shall
be the broadcast PAN identifier (0xFFFF).

4.

If a short destination address is included in the frame, it shall match either
macShortAddress or the broadcast address (0xFFFF). Otherwise, if an extended
destination address is included in the frame, it shall match aExtendedAddress.

5.

If the frame type indicates that the frame is a beacon frame, the source PAN identifier
shall match macPANId unless macPANId is equal to 0xFFF, in which case the beacon
frame shall be accepted regardless of the source PAN identifier.

6.

If only source addressing fields are included in a data or MAC command frame, the
frame shall be accepted only if the device is the PAN coordinator and the source PAN
identifier matches macPANId.

The AT86RF231 requires satisfying two additional rules:

7.

The frame type indicates that the frame is not an ACK frame (refer to

Table 8-4 on page

82

).

8.

At least one address field must be configured.