OpenParcelBox/hardware/pinout.md

OpenParcelBox Pinout

This document records the current hardware pin assignments.

It is the reference for:

• Zephyr firmware.
• KiCad schematics.
• PCB design.

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Microcontroller

Seeed Studio XIAO BLE nRF52840

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Current Development Pin Assignments

Function	Direction	Pin	Notes
Active buzzer control	Output	D0	GPIO signal to transistor driver
PCF8574 I2C SDA	I/O	SDA	Development keypad GPIO expander
PCF8574 I2C SCL	Output	SCL	Development keypad GPIO expander
RGB LED red	Output	Board LED alias led0	On-board validation LED
RGB LED green	Output	Board LED alias led1	On-board validation LED
RGB LED blue	Output	Board LED alias led2	On-board validation LED

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Planned Production Assignments

These signals still need to be assigned after hardware validation:

• Lock SIG command.
• Lock COM/NC feedback.
• Production keypad matrix.
• NFC antenna and matching network.
• Battery voltage measurement.
• External status LEDs.
• Additional expansion signals.

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Any modification to this document must be reflected in:

• The firmware board configuration.
• The KiCad schematic.
• The PCB design.