BU03-Kit Development Board (Hardware Section 2)

——AndyL

3. Functional Effectiveness Testing

1. Quick Start Test

UART 1

1. Connect a Type-C data cable to your PC, open a serial terminal tool, and press the reset button. If the terminal prints the expected boot messages, the reset button works properly.

  • Send the command AT; if you receive OK, the send/receive test passes.

USB

The USB port is the TypeC connector labeled USB on the BU03Kit, used for printing distance measurements and other info. It uses the STM MCU’s builtin USB driver. Windows and macOS usually won’t auto-install this driver, so you must manually install it.

 

UART2

Testing UART2 requires a USBtoTTL adapter. UART2 will output ranging data (covered in later sections).

Wiring for USB to TTL adapter:

BU03Kit Pin

Adapter Pin

3V3

3V3

GND

GND

PA2 (TX)

RX

PA3 (RX)

TX

 

LED Flow Test

Connect to the TTL port and send:

AT+TESTLED=X

Parameter

Description

X = 1

Start LED flow test

X = 0

Stop LED flow test

Response:

  • OK — AT command succeeded
  • ERR — AT command failed
  • Send:    AT+TESTLED=1
  • Receive: OK
  • Configure one BU03Kit as anchor, another as tag.
  • Anchor’s OLED or USB port will display the current distance to the tag.
  • Keep antennas unobstructed and tags off flat surfaces to minimize error.
  • For higher precision, use the calibration command (below).

Example:

 

2. UWB Function Tests

Distance Only (Zeropoint) & 1D Positioning

With one anchor and multiple tags, you get realtime distance measurements (no direction). Adding a second anchor lets you compute onedimensional positions along a line.

 

2D Positioning (3 Anchors)

Three anchors plus tags yield basic 2D positioning. If one anchor is blocked or interfered, loss of redundancy hurts accuracy. Ensure clear lineofsight between anchors and tags.

You only need any one module (anchor or tag) to stream positioning data via USB/UART/WiFi/Ethernet to a PC; other anchors just need power and will forward data wirelessly.

 

Improved 2D (4 Anchors)

Four anchors add redundancy: if one is blocked, the extra data preserves accuracy. Same lineofsight requirement and streaming setup applies.

 

3D Positioning (6+ Anchors)

Six or more anchors support largearea 2D or full 3D positioning, with robust redundancy under blockage. Same streaming and power requirements.

 

Common AT Commands

Command

Description

Response

Example

AT+SETUWBMODE=X

Select algorithm (must save after): 0 = TWR, 1 = PDOA

OK/ERR

Send AT+SETUWBMODE=0 → OK

AT+GETUWBMODE

Query current algorithm

OK/ERR

Send AT+GETUWBMODE → twr_pdoa_mode: 0 OK

AT+SAVE

Save current configuration

OK/ERR

Send AT+SAVE → OK

AT+SETCFG=X1,X2,X3,1

Set config (then save):- X1 = Device ID (0–10)- X2 = Role (0=Tag, 1=Anchor)- X3 = Channel (0=ch9, 1=ch5)- Rate fixed at 6.8 Mbps

OK/ERR

Send AT+SETCFG=0,1,0,1 → setcfg ID:0, Role:1, CH:0, Rate:1 OK

AT+RESTORE

Restore factory defaults

OK/ERR

Send AT+RESTORE → OK

 

TWR Algorithm: Ranging & Positioning

Setup

 

Ranging Steps

  • On Anchor (A):
  • On Tag (B):

AT+SETUWBMODE=0

AT+SETCFG=0,1,1,1

AT+SAVE

AT+SETUWBMODE=0

AT+SETCFG=0,0,1,1

AT+SAVE

 

Anchor’s OLED shows distance to Tag.

 

Observed without calibration: ±20 cm fluctuation.

 

2D Positioning

  • Use three anchors and one tag.
  • After configuring all, open the TWR PC software, connect any anchor via USB, and view realtime 20 m range navigation and track display.
  • If USB isn’t recognized, restart software or replug the cable.
  • Place anchors ≥1.5 m high with clear lineofsight (tripods recommended).

 

 

PDOA Algorithm: Ranging...

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