Hardware.md

Hardware

• RFID (SPI0)
• RGB-DMD (I2C0 level shifted)
• WS2812 (GPIO level shifted)
• Magnetometer (I2C0)
• WiFi with power control (UART1 + GPIO)
• Sound-Player (UART0)
• Multi-target sensor VL53L3X (I2C0)
• Motor driver TB66FNG (GPIO + PWM)
• Line tracker (ADC + GPIO)
• Personality I2C EEPROM 24FC01T (I2C0)
• Battery voltage measurement (ADC2)
• Battery supply: 5V and 3V3 regulators, Motor-Driver (motor power)
• 5V power supply @ 2.5A: Raspberry Pi Pico, RGB-DMD, WS2812, Sound-Player, WiFi
• 3V3 pico supply @ 300mA: Motor-Driver (just logic), RFID, Magnetometer, VL53L3X, Line tracker, EEPROM, other logic ICs

TODO

• Add accelerometer to this document
• Print replacement arrow label for WiFi header on PCB
• Assemble PCBs
• Make custom cables

Block diagram

Pin allocation

• SPI0: 3 (MOSI0, MISO0, SCK0) + 2 (RFID_SS, RFID_IRQ)
• I2C0: 2 (SDA0, SCL0)
• UART0: 2 (RX0, TX0) + 2 (WIFI_ENABLE, WIFI_FAULT)
• UART1: 2 (RX1, TX1) + 1 (PLAYER_BUSY)
• WS2812: 2 (GPIO level shifted)
• Motor driver: 2 (PWM) + 5 (GPIO)
• Line tracker: 2 (ADC + GPIO)
• Battery supervision: 1 (ADC)
• Heartbeat LED: 1 (Pin 25 internal)

Total used/available: 27/27 (all used)

Pico Pinout

• GP0: OUT: MOTOR_PWMB
• GP1: OUT: MOTOR_BI2
• GP2: OUT: MOTOR_BI1
• GP3: OUT: MOTOR_STBY, active-low
• GP4: OUT: MOTOR_AI1
• GP5: OUT: MOTOR_AI2
• GP6: OUT: MOTOR_PWMA
• GP7: INP: RFID_IRQ, probably unused, int-pullup or int-pulldown as configured, could be reset output instead
• GP8: OUT: WIFI_TX
• GP9: INP: WIFI_RX
• GP10: OUT: RFID_CK
• GP11: INP: RFID_TX
• GP12: OUT: RFID_RX, int-pulldown
• GP13: OUT: RFID_CD
• GP14: INP: WIFI_FAULT, active-low, int-pullup
• GP15: OUT: WIFI_ENABLE, active-high
• GP16: OUT: SOUND_TX
• GP17: INP: SOUND_RX, int-pullup
• GP18: OUT: WS2812_A
• GP19: OUT: WS2812_B
• GP20: BID: I2C0_SDA
• GP21: OUT: I2C0_SCL
• GP22: INP: SOUND_BUSY, int-pullup, high = idle, low = playing
• GP23: OUT: 3V3 SMPS power save mode
• GP24: INP: VBUS sense (is USB plugged in)
• GP25: OUT: Heartbeat LED
• GP26: ADC: LINE_REFLECTANCE
• GP27: OUT: LINE_ENABLE
• GP28: ADC: VBAT minus drop over U3, then divided
• GP29: ADC: VSYS/3 = 5V SMPS / 3

RFID

SPI

The sensor is absolute garbage. Minimum read distance is 2cm. Reliable read distance is 1cm. UUID detection distance is 4cm.

https://www.berrybase.de/rfid-lesegeraet-mit-spi-schnittstelle-inkl.-karte-dongle

• MOSI
• MISO
• SCK
• SS
• IRQ/RESET
• 3V3

RGB-DMD

13x9 RGB565, I2C

https://www.berrybase.de/adafruit-is31fl3741-13x9-pwm-rgb-led-matrix-treiber

• SDA
• SCL
• Power at 5V (looks better) and use I2C level shifter (could be powered at 3V3, but looks better at 5V)

WS2812

WS2812 (level shifted to 5V), 60 LED/m, 60mAp/LED, Protection series resistor 330R, 100-1000uF decoupling

Shield: 63cm -> 37 LEDs, 2.22Ap, 3mm spaced from top of shield

Cannon: TBD

• OUT1
• OUT2
• 5V

Magnetometer

I2C

https://www.berrybase.de/adafruit-drei-achsen-magnetometer-lis3mdl

• SDA
• SCL
• 3V3

WiFi

UART, Firmware update passthrough

• RX
• TX
• ENABLE
• FAULT
• 3V3

Personality I2C EEPROM 24FC01T

I2C

https://www.tme.eu/de/details/24fc01t-i_ot/serielle-eeprom-speicher/microchip-technology/

• SDA
• SCL
• 3V3

Sound Player

UART @ 9600 8N1

https://www.berrybase.de/mp3-player-modul-mit-eingebautem-verstaerker

• RX
• TX
• 5V

Multi-target sensor VL53L3X

I2C

https://www.berrybase.de/pololu-vl53l3cx-time-of-flight-multi-target-distanzsensor-mit-spannungsregler-bis-500cm

• SDA
• SCL
• 3V3

Motor driver TB66FNG

PWM GPIO

https://www.berrybase.de/sparkfun-motor-treiber-dual-tb6612fng-mit-headern

• PWMA (SPEED1)
• PWMB (SPEED2)
• AIN1 (DIR1)
• AIN2 (DIR1)
• BIN1 (DIR2)
• BIN2 (DIR2)
• STBY
• 3V3
• 8V

Line tracker

ADC GPIO

https://www.pololu.com/product/4641

• Analog signal pin
• Control pin
• 3V3