DW1000 User Manual
© Decawave Ltd 2017
Version 2.12
Page 103 of 242
Antenna Delay
for details of calibration of antenna delay. The units here are the same as those used for
system time and time stamps, i.e. 499.2 MHz × 128, so the least significant bit is about 15.65 picoseconds.
NB:
This register is not preserved during
or
and so needs reprogramming after a
wakeup event in order to obtain the correct adjustment of the TX_STAMP.
The TX_ANTD is corrupted during wake-up (assuming the ONW_LDC bit in
is set to restore configurations) the high-octet of the receive antenna delay as
Sub-Register 0x2E:1804 – LDE_RXANTD
overwrites the low-octet of TX_ANTD.
7.2.27 Register file: 0x19
– Reserved
ID
Length
(octets)
Type
Mnemonic
Description
0x19
5
RO
SYS_STATE
System State information
register file 0x19 is reserved.
7.2.28 Register file: 0x1A
– Acknowledgement time and response time
ID
Length
(octets)
Type
Mnemonic
Description
0x1A
4
RW
ACK_RESP_T Acknowledgement Time and Response Time
register file 0x1A is a configuration register used for specifying turn-around times for DW1000
to use when automatically switching between TX mode and RX modes. The ACK_RESP_T register contains
the following bitmapped sub-fields:
REG:1A:00 – ACK_RESP – RX Frame Information
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
ACK_TIM
- - - -
W4R_TIM
0
0 0 0 0
0
The individual sub-fields are described below:
Field
Description of fields within Register file: 0x1A – Acknowledgement time and response time
W4R_TIM
reg:1A:00
bits:19–0
Wait-for-Response turn-around Time. This 20-bit field is used to configure the turn-around
time between TX complete and RX enable when the wait for response function is being used.
This function is enabled by the WAIT4RESP control in
Register file: 0x0D – System Control
. The time specified by this W4R_TIM parameter is in units of approximately 1 µs, or
128 system clock cycles. This configuration may be used to save power by delaying the turn-on
of the receiver, to align with the response time of the remote system, rather than turning on
the receiver immediately after transmission completes. For more details see section
5.4 –