Regarding git hub example

Wireless Connectivity Ultra-Wideband
1

hello,
we are using a customised module with dw,nrf52832 and accelarometer and i am using this git hub example dwm1001-examples/main.c at master · Decawave/dwm1001-examples · GitHub flasing initator code in one board and responder in other but whenever i attempt to change the preamble length to 1024 and and data rate to 110 k i could not calculate the distance ?does anyone know the reason for this problem
static dwt_config_t config = {
5, /* Channel number. /
DWT_PRF_16M, / Pulse repetition frequency. /
DWT_PLEN_1024, / Preamble length. Used in TX only. /
DWT_PAC32, / Preamble acquisition chunk size. Used in RX only. /
3, / TX preamble code. Used in TX only. /
3, / RX preamble code. Used in RX only. /
1, / 0 to use standard SFD, 1 to use non-standard SFD. /
DWT_BR_110k, / Data rate. /
DWT_PHRMODE_STD, / PHY header mode. /
(1024 + 8- 32) / SFD timeout (preamble length + 1 + SFD length - PAC size). Used in RX only. */
};this configuration does not work

static dwt_config_t config = {
5, /* Channel number. /
DWT_PRF_16M, / Pulse repetition frequency. /
DWT_PLEN_128, / Preamble length. Used in TX only. /
DWT_PAC32, / Preamble acquisition chunk size. Used in RX only. /
3, / TX preamble code. Used in TX only. /
3, / RX preamble code. Used in RX only. /
1, / 0 to use standard SFD, 1 to use non-standard SFD. /
DWT_BR_6M8, / Data rate. /
DWT_PHRMODE_STD, / PHY header mode. /
(129 + 8- 32) / SFD timeout (preamble length + 1 + SFD length - PAC size). Used in RX only. */
};
but this does not work
kindly help me with this
thanks and regards
manikandan v

2

by increasing the PLEN and decreasing of Datarate, you are increasing the length on the frame which is transmitted over the air. you need to increase timings in the TWR examples such they would be longer than the frame lengths.

3

thanks for your reply
configuration
static dwt_config_t config = {
2, /* Channel number. /
DWT_PRF_64M, / Pulse repetition frequency. /
DWT_PLEN_1024, / Preamble length. Used in TX only. /
DWT_PAC32, / Preamble acquisition chunk size. Used in RX only. /
9, / TX preamble code. Used in TX only. /
9, / RX preamble code. Used in RX only. /
1, / 0 to use standard SFD, 1 to use non-standard SFD. /
DWT_BR_110K, / Data rate. /
DWT_PHRMODE_STD, / PHY header mode. /
(1025 + 64 - 32) / SFD timeout (preamble length + 1 + SFD length - PAC size). Used in RX only. */
};
init side
POLL_TX_TO_RESP_RX_DLY_UUS 10000
responder side
POLL_RX_TO_RESP_TX_DLY_UUS 12000

i did this changes but i am getting the values in negative with any accuracy can you tell me how can i rectify this
thanks and regards
manikandan v