Here are the connections I made 😃:
XIAO ESP32-C3
| XIAO Pin |
Connects To |
Type |
| D0 (GPIO2) |
Front VL53L1X XSHUT |
Signal |
| D1 (GPIO3) |
Left VL53L1X XSHUT |
Signal |
| D2 (GPIO4) |
Right VL53L1X XSHUT |
Signal |
| D3 (GPIO5) |
VL53L1X SDA |
I2C |
| D4 (GPIO6) |
VL53L1X SCL |
I2C |
| D5 (GPIO7) |
DFPlayer TX |
UART RX |
| D6 (GPIO21) |
Left MD20A PWM |
Motor Control |
| D7 (GPIO20) |
Left MD20A DIR |
Motor Control |
| D8 (GPIO8) |
Right MD20A PWM |
Motor Control |
| D9 (GPIO9) |
Right MD20A DIR |
Motor Control |
| D10 (GPIO10) |
DFPlayer RX (through 1kΩ resistor) |
UART TX |
Front VL53L1X Sensor
| Sensor Pin |
Connects To |
Type |
| VCC |
3.3V |
Power |
| GND |
GND |
Ground |
| SDA |
D3 (GPIO5) |
I2C |
| SCL |
D4 (GPIO6) |
I2C |
| XSHUT |
D0 (GPIO2) |
Signal |
Left VL53L1X Sensor
| Sensor Pin |
Connects To |
Type |
| VCC |
3.3V |
Power |
| GND |
GND |
Ground |
| SDA |
D3 (GPIO5) |
I2C |
| SCL |
D4 (GPIO6) |
I2C |
| XSHUT |
D1 (GPIO3) |
Signal |
Right VL53L1X Sensor
| Sensor Pin |
Connects To |
Type |
| VCC |
3.3V |
Power |
| GND |
GND |
Ground |
| SDA |
D3 (GPIO5) |
I2C |
| SCL |
D4 (GPIO6) |
I2C |
| XSHUT |
D2 (GPIO4) |
Signal |
DFPlayer Mini
| DFPlayer Pin |
Connects To |
Type |
| VCC |
5V rail |
Power |
| GND |
GND |
Ground |
| RX |
D10 through 1kΩ resistor |
UART |
| TX |
D5 |
UART |
Speaker
| Speaker Pin |
Connects To |
Type |
| + |
DFPlayer SPK1 |
Audio |
| − |
DFPlayer SPK2 |
Audio |
Left MD20A Motor Driver
| MD20A Pin |
Connects To |
Type |
| PWM |
D6 (GPIO21) |
PWM |
| DIR |
D7 (GPIO20) |
Direction |
| VIN |
BAT+ |
Motor Power |
| GND |
GND |
Ground |
| MOTOR A |
Left Motor + |
Motor Output |
| MOTOR B |
Left Motor − |
Motor Output |
Right MD20A Motor Driver
| MD20A Pin |
Connects To |
Type |
| PWM |
D8 (GPIO8) |
PWM |
| DIR |
D9 (GPIO9) |
Direction |
| VIN |
BAT+ |
Motor Power |
| GND |
GND |
Ground |
| MOTOR A |
Right Motor + |
Motor Output |
| MOTOR B |
Right Motor − |
Motor Output |
Inter-Board Connector
| Pin |
Signal |
Type |
| 1 |
5V |
Power |
| 2 |
GND |
Ground |
| 3 |
LEFT_PWM (GPIO21) |
Signal |
| 4 |
LEFT_DIR (GPIO20) |
Signal |
| 5 |
RIGHT_PWM (GPIO8) |
Signal |
| 6 |
RIGHT_DIR (GPIO9) |
Signal |
| 7 |
3.3V |
Power |
| 8 |
Spare / Enable |
Signal |
11.1V LiPo Battery
| Battery Pin |
Connects To |
Type |
| B+ |
Fuse → Switch → SS34 Diode → BAT+ Rail |
Power |
| B− |
GND Rail |
Ground |
LM2596 Buck Converter
| LM2596 Pin |
Connects To |
Type |
| IN+ |
BAT+ |
Power Input |
| IN− |
GND |
Ground |
| OUT+ |
5V Rail |
Power Output |
| OUT− |
GND |
Ground |
Resistors
| Resistor |
Connection |
Purpose |
| 1kΩ |
D10 → DFPlayer RX |
UART Protection |
Capacitors
| Capacitor |
Connection |
Purpose |
| 470µF 25V |
BAT+ ↔ GND |
Bulk Filtering |
| 100µF 25V |
LM2596 IN+ ↔ IN− |
Input Filtering |
| 470µF 10V |
5V ↔ GND |
Main Smoothing |
| 100nF |
Across Motor Terminals |
Noise Suppression |
Common Ground Connections
| Component |
Connects To |
| Battery − |
Common GND |
| XIAO GND |
Common GND |
| LM2596 IN− / OUT− |
Common GND |
| Both MD20A GNDs |
Common GND |
| DFPlayer GND |
Common GND |
| All VL53L1X GNDs |
Common GND |