DW1000 User Manual
© Decawave Ltd 2017
Version 2.12
Page 221 of 242
11.2 The frame control field in the MAC header
The frame control field is a two-octet (16-bit) field that begins every IEEE 802.15.4 MAC frame. Its role is to
identify the frame type and indicate what components are incorporated in the remainder of the MAC
header. Figure 35 shows the frame control this and identifies the sub-fields within it. These are described
below.
Figure 35: MAC message frame control field
11.2.1 Frame type field
This frame type field is a 3-bit field that indicates the type of frame. Table 62 below lists the eight possible
frame types and their assignment in IEEE 802.15.4-2011.
Table 62: Frame type field values
Frame Type Field
(FC bits 2 to 0)
Frame
0, 0, 0
Beacon
0, 0, 1
Data
0, 1, 0
Acknowledgement
0, 1, 1
MAC command
1, 0, 0
Reserved
1, 0, 1
Reserved
1, 1, 0
Reserved
1, 1, 1
Reserved
While only four of the eight frame types are assigned by IEEE 802.15.4-2011, some of the reserved types
have since been allocated within the IEEE 802.15 Working Group for special applications. The DW1000
provides only minimal support for the new frame types by allowing their acceptance to be enabled within
the frame filtering function. Please refer to section
for details. If these new frames are
enabled then the host system will need to parse the received frames to validate each of them including
checking that the destination address is correct and the host system will need to initiate the transmission of
any acknowledgement response required.
11.2.2 Security enabled Field
This bit when set indicates the presence of the Auxiliary Security Header field within the MAC header and
indicates that the MAC may be employing security processing of the frame payload for authentication
and/or encryption. The DW1000 does not incorporate any facilities for security, so if the frame is
Frame
Type
Bits
0 to 2
Security
Enabled
Bit
3
Frame
Pending
Bit
4
ACK
Request
Bit
5
PAN ID
Compress
Bit
6
Reserved
Bits
7 to 9
Dest.
Address
Mode
Bits
10 & 11
Frame
Version
Bits
12 & 13
Source
Address
Mode
Bits
14 & 15