Rainbow Electronics AT86RF231 User Manual
Page 81

81
8111A–AVR–05/08
AT86RF231
• Bit [2:0]:
describe the frame type.
summarizes frame types defined by IEEE
802.15.4, section 7.2.1.1.1.
This subfield is used for address filtering by the third level filter rules. Only frame types 0 - 3 pass
the third level filter rules, refer to
Section 7.2.3.5 “Frame Filtering” on page 61
Automatic address
filtering by the AT86RF231 is enabled when using the RX_AACK mode, refer to
“RX_AACK_ON - Receive with Automatic ACK” on page 51
.
However, a reserved frame (frame type value > 3) can be received if register bit
AACK_UPLD_RES_FT (register 0x17, XAH_CTRL_1) is set, for details refer to
“Configuration of non IEEE 802.15.4 Compliant Scenarios” on page 58
.
Address filtering is also provided in Basic Operating Mode, refer to
• Bit 3:
indicates whether security processing applies to this frame.
• Bit 4:
is the "Frame Pending" subfield. This field can be set in an acknowledgment frame (ACK) in
response to a data request MAC command frame. This bit indicates that the node, which trans-
mitted the ACK, has more data to send to the node receiving the ACK.
For acknowledgment frames automatically generated by the AT86RF231, this bit is set accord-
ing to the content of register bit AACK_SET_PD in register 0x2E (CSMA_SEED_1) if the
received frame was a data request MAC command frame.
• Bit 5:
forms the "Acknowledgment Request" subfield. If this bit is set within a data or MAC command
frame that is not broadcast, the recipient shall acknowledge the reception of the frame within the
time specified by IEEE 802.15.4 (i.e. within 192 µs for non beacon-enabled networks).
The radio transceiver parses this bit during RX_AACK mode and transmits an acknowledgment
frame if necessary.
In TX_ARET mode this bit indicates if an acknowledgement frame is expected after transmitting
a frame. If this is the case, the receiver waits for the acknowledgment frame, otherwise the
TX_ARET transaction is finished.
Table 8-2.
Frame Control Field - Frame Type Subfield
Frame Control Field Bit Assignments
Description
Frame Type Value
b
2
b
1
b
0
Value
000
0
Beacon
001
1
Data
010
2
Acknowledge
011
3
MAC command
100 - 111
4 - 7
Reserved