PebbleOS BangleJS2 Port

This is a port of PebbleOS to the BangleJS2 smartwatch.

Prerequisites

• Docker - For building firmware in a consistent environment
• probe-rs - For flashing firmware via SWD (cargo install probe-rs-tools)
• Rust toolchain - For building QSPI flasher tools and memory logger (curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh)
• Python 3 - For QSPI flash image creation

Quick Start

# Clone the repository
git clone --recursive <repository-url>
cd pebbleos-banglejs2

# Initialize submodules (if not cloned with --recursive)
make init-submodules

# Build everything
make build

# Build and flash (requires hardware connected via SWD)
make flash

Repository Structure

This is a metarepo containing references to all repositories needed for the BangleJS2 port:

• PebbleOS - Main firmware (branch: banglejs2)
• nrfx - Nordic RF driver (branch: pebbleos-banglejs2)
• pebbleapp - Companion phone app (branch: banglejs2)
• qspi-flasher - QSPI flashing tooling
• bangle-memory-logger - Memory-based log reading tooling

What's Working

• Watch functionality
• Good battery life (~20%/day)
• Color display
• Touch emulated as button
• Sleep mode
• Vibration motor (PWM-based)
• QSPI flash access

What's Not Working

• Peripherals (accelerometer, GPS, heart rate sensor, temperature, pressure, etc.)

Building with Makefile

Initialize submodules:

make init-submodules

Build firmware only:

make build-firmware

Build all tools (QSPI flasher + memory logger):

make build-tools

Build everything:

make build

Clean build artifacts:

make clean

Build and Flash Options

Using Makefile (Recommended)

Flash everything (requires hardware):

make flash

Flash QSPI only:

make flash-qspi

Flash main firmware only:

make flash-firmware

Read logs (requires hardware):

make logs

Using Shell Script

A convenience script is provided in scripts/build_and_flash.sh:

./scripts/build_and_flash.sh

Options:

• --no-flash - Build only, skip all flashing
• --no-qspi - Skip QSPI flash, only flash main firmware

Manual Tool Building

If not using the Makefile:

QSPI flasher:

# Firmware
cd qspi-flasher/qspi-flasher-fw
cargo build --release

# Host tool
cd qspi-flasher/qspi-flasher-host
cargo build --release

Memory logger:

cd bangle-memory-logger
cargo build --release

Flashing

The device must be connected via SWD and powered on. Use probe-rs for flashing:

# Flash main firmware
probe-rs download --chip nRF52840_xxAA PebbleOS/build/src/fw/tintin_fw.elf
probe-rs reset --chip nRF52840_xxAA

For QSPI flashing, use the qspi-flasher tooling (see make flash-qspi).

Reading Logs

The bangle-memory-logger tool reads log buffers from the device via SWD:

./bangle-memory-logger/target/release/log-reader --elf PebbleOS/build/src/fw/tintin_fw.elf | tee output.log

Options:

• --elf <path> - Path to the firmware ELF file (for symbol resolution)
• Use tee to both display and save logs

The device must be connected via SWD and powered on.

Notes

• Only SWD port is exposed on BangleJS2, requiring special tooling for QSPI flashing
• Memory buffer logging is used for debugging via SWD
• nrfx fork includes LOG_BUFFER memory region changes for host-accessible logging