Download ZWIR4501

Transcript
ZWIR4501
CoordAddrCheck
If this bit is set, then the source address of the incoming beacon is compared to the coordinator address stored
in the macCoordSrcAddr1..2 or macCoordExtAddr1..8 register, in addition to the frame filter rules defined in
IEEE 802.15.4, Section 7.5.6.2. If the source address of the beacon does not match, a PAN identifier conflict is
likely and the beacon is not accepted. For details about the coordinator address check and PAN identifier conflict
resolution refer to IEEE 802.15.4, Section 7.5.2.2 and 7.5.4.1.
A failing coordinator address check is indicated in the macBcTrStatus register. Note that beacon frames failing
the coordinator address check are still stored in the RxFIFO for further processing by the firmware. If the
CoordAddrCheck bit is not set, the source address of beacon frames is not compared to the coordinator
address.
AlignEnable
This bit enables the integrated beacon interval timing correction. After each tracked beacon, the tracking error is
derived and used to correct the next beacon interval duration. This timing correction reduces the timing drift
between a coordinator and a device caused by different crystal frequency offsets.
Register: MAC Beacon Track Status [6:0]
mnemonic: macBcTrStatus,
MAC_BTR_STATUS
address
Addr.
Status
0xA7
Register
macBcTrStatus
0xA7,
access
R,
C
code-based
constant address
Description
0x00 Off
Beacon tracking is off
0x01 Track
Tracking (waiting until the expected arrival of the
next beacon, then starting scan for the beacon)
0x02 Scan
Scanning for the next beacon
0x04 SyncLoss*
Loss of synchronization (number
macMaxLostBeacons of consecutive beacon
missed)
0x08 Beacon*
Beacon successfully tracked
0x10
CorrdAddrFail
Beacon tracked with wrong SrcAddr (possible
macPanID conflict)
0x20 Sync
Initial beacon tracked
0x40 Align
Consecutive beacon tracked (automatic timing
correction is active)
definition:
Reset
0x00
* Status indicated by the IRQ
The macBcTrStatus register monitors the beacon track status. The loss of synchronization and the arrival
tracking of a beacon are indicated by interrupts. For details, refer to the beacon tracking mode description
section 4.11.6.
Copyright © 2009, ZMD AG, ZWIR4501 Data Sheet and User Manual v.1.3 - August 19, 2009
Page 102 of 124