Table 7: Registers in the RX double-buffered swinging-set
RX double-buffered registers
LDEDONE, RXDFR, RXFCE and RXFCG bits in Register file: 0x0F – System Event Status Register
All of Register file: 0x10 – RX Frame Information Register
All of Register file: 0x11 – RX Frame Buffer
All of Register file: 0x12 – Rx Frame Quality Information
All of Register file: 0x13 – Receiver Time Tracking Interval
All of Register file: 0x14 – Receiver Time Tracking Offset
All of Register file: 0x15 – Receive Time Stamp
4.3.1 Enabling double-buffered operation
By default the DW1000 operates in a single buffered mode that is appropriate for many applications. When
using double-buffered mode it is appropriate to also configure the DW1000 to automatically re-enable the
receiver (moving on to the other buffer of the swinging set) as soon as it has completed receiving any
previous frame. Double-buffered receiving is enabled by setting the DIS_DRXB bit to zero, (in Register file:
0x04 – System Configuration). The RX auto-re-enable function is enabled by setting the RXAUTR bit to 1 (in
Register file: 0x04 – System Configuration).
DW1000 may be operated in double buffered mode without automatically re-enabling the receiver also,
which requires the host to manually enable the receiver to receive the next frame. The receiver can be
enabled in advance of processing the previously received frame. This operation will reduce the amount of
time for which the receiver may be actively listening for frames on the air, but will prevent both buffers
being full (at the same time) and will prevent overflows. This simplifies the buffer operation, see sections
4.3.3 and 4.3.5.
Note: When enabling or re-enabling the receiver in double-buffered mode, it is important to align both host
and IC receivers. That is, it is important to ensure that the buffer set that the IC receiver will first receive
into is the same set that the host system is pointing to and will first process when the first frame arrives.
Please refer to section 4.3.2 below for a discussion of this and how to achieve it.
4.3.2 Controlling which buffer is being accessed
There are two register sets, register-set-0 and register-set-1, but the host may only access one set at a time
through the register addresses listed in Table 7. To swap between sets the host issues the HRBPT (Host Side
Receive Buffer Pointer Toggle) command in Register file: 0x0D – System Control Register. The register-set
currently being accessed is reported by the HSRBP (Host Side Receive Buffer Pointer) status bit in Register
file: 0x0F – System Event Status Register. Every time the HRBPT command is issued the HSRBP status bit will
toggle.
There is also a read-only IC side buffer pointer index indicating which register-set the IC receiver is using or
will use for the next frame received, this is the ICRBP status bit (also in Register file: 0x0F – System Event
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