2.5.3 Default Transmitter Configuration
Transmit RF channel configurations are set for channel 5 by default – see Sub-Register 0x28:0C– RF_TXCTRL.
Transmit Smart power is enabled by default via the DIS_STXP bit in SYS_CFG register, refer to Register file:
0x04 – System Configuration. Please see section 7.2.31.2 – Smart Transmit Power Control for further
information.
The transmit preamble symbol repetition length is 128 symbols, see Register file: 0x08 – Transmit Frame
Control, TXPSR and PE fields for configuration details.
2.5.4 Default Receiver Configuration
Receiver RF channel configurations are set for channel 5 by default, see Sub-Register 0x28:0B– RF_RXCTRLH.
Digital receiver tuning registers; DRX_TUNE0b, DRX_TUNE1a, DRX_TUNE1b and DRX_TUNE2 are configured
by default for 16 MHz PRF, 6.8 Mbps data rate and a preamble symbol repetition of length 128. See Sub-
Register 0x27:02 – DRX_TUNE0b, Sub-Register 0x27:04 – DRX_TUNE1a, Sub-Register 0x27:06 – DRX_TUNE1b
and Sub-Register 0x27:08 – DRX_TUNE2 for programming details.
The LDERUNE bit is enabled by default, which means that the microcode (the LDE algorithm) that has been
loaded in RAM will execute on every frame reception, which in turn will calculate accurate frame time-of-
arrival. However the DW1000 needs to load this microcode on power-on from a special ROM area in the
DW1000. This is done by enabling the LDELOAD bit as part of DW1000 initialisation (because after powering
up the DW1000 (or after exiting SLEEP or DEEPSLEEP states) the LDE RAM is empty). This should be done
before the receiver is enabled if it is important to timestamp this received frame. If the LDE code is not
being loaded before the receiver is enabled then the LDERUNE (LDE run enable) control in Sub-Register
0x36:04 – PMSC_CTRL1 must be turned off (set to zero).
2.5.5 Default Configurations that should be modified
Although the DW1000 will power up in a usable mode for the default configuration outlined, some of the
register defaults are sub optimal and should be overwritten before proceeding to use the device in the
default mode.
2.5.5.1 AGC_TUNE1
AGC_TUNE1 is set to 0x889B by default which is not the optimal value for the default PRF of 16 MHz. For
best performance the user should set this value to 0x8870 before proceeding to use the default device
configuration. Refer to Sub-Register 0x23:04 – AGC_TUNE1.
2.5.5.2 AGC_TUNE2
AGC_TUNE2 must be set as described in Sub-Register 0x23:0C – AGC_TUNE2 for correct functioning of
DW1000.
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