M45 Core Firmware

M45 Core Firmware is ESP-IDF firmware for ESP32 boards that run a plain-TCP Stratum SHA-256 miner, local web setup UI, and either a small OLED or ideaspark LCD status display.

Currently, on target hardware this averages about 620 Kh/s

Open the browser firmware flasher or read flashing details.

Supported Hardware

• Primary chip: ESP32-WROOM-32 or another classic ESP32 target with hardware SHA.
• Compatibility chip: ESP32-S3-WROOM source build using the software miner and the default SSD1306 wiring.
• Default display: SSD1306 128x64 I2C OLED at address 0x3c.
• OLED pins: SDA GPIO5, SCL GPIO4, reset GPIO16.
• Unsupported OLED lookalikes: ESP32 OLED boards wired to SDA GPIO21 and SCL GPIO22 need a custom build or firmware port.
• LCD build: ideaspark ESP32 1.9 inch LCD with ST7789 controller, 320x170.
• Unsupported LCD lookalikes: ESP32-C3, ESP32-S3 LCD, and ESP32-1732S019 boards need a separate display port and cannot run the current release binaries.
• Classic ESP32 flash: 4 MB layout with bootloader at 0x1000, partition table at 0x8000, settings/NVS at 0x9000..0xEFFF, and app at 0x10000.
• ESP32-S3 source build: bootloader at 0x0, partition table at 0x8000, and app at 0x10000.

OLED Display	ideaspark 1.9 inch LCD	Web Stats	Web Settings

Example block-found screens

Buy Links

Prices change by region, shipping destination, selected variant, coupons, and account state. Check each listing directly before ordering.

Firmware build	Source	Listing	Price	Note
OLED/default	Amazon	SSD1306 128x64 I2C OLED	US $11.99	Supported OLED board.
LCD	Amazon	ideaspark ESP32 1.9 inch LCD	US $15.99	Supported ideaspark LCD board.

Firmware Features

• First-boot setup access point with captive portal helpers and Wi-Fi scanning.
• Web UI for live mining stats, pool settings, display settings, reboot, and factory reset.
• Display pages for setup QR, Wi-Fi/IP status, pool status, hashrate, shares, best share, and block-found alerts.
• Primary and backup Stratum pool support with configurable host, port, worker, wallet, and suggested difficulty.
• Coinbase payout visibility in the stats UI when pool job data can be checked.
• CPU performance mode, display sleep, brightness, flip, theme, and LCD text outline controls.
• Browser flasher that verifies release checksums and can preserve existing Wi-Fi and pool settings during upgrades.

Current Build Snapshot

These figures are from a local v0.0.5 build with ESP-IDF v5.5.3.

Build	App binary	IRAM	DRAM
OLED/default	725.41 KiB	107.97 KiB	52.37 KiB
ideaspark LCD	956.97 KiB	112.08 KiB	107.89 KiB
synthetic benchmark	701.58 KiB	84.90 KiB	51.77 KiB

Host-visible source and web/script support code is roughly 15k lines.

Requirements

• Official ESP-IDF checkout, tested with ESP-IDF v5.5.3.
• Python 3.
• git for the ESP-IDF setup helper.
• Pillow only when building LCD image/font assets for the ideaspark LCD target.
• Chrome or Edge on desktop for Web Serial browser flashing.

PlatformIO-packaged ESP-IDF is intentionally rejected by the helper scripts. Use the official ESP-IDF checkout, or set IDF_PATH / IDF_EXPORT_SCRIPT to one.

Quick Start

Install or verify ESP-IDF:

./scripts/setup-esp-idf.sh
./scripts/check-environment.sh

Build the default OLED firmware:

./scripts/build-firmware.sh

Build the ideaspark LCD firmware:

./scripts/build-firmware.sh --ideaspark-19-lcd

Flash through ESP-IDF:

./scripts/flash-firmware.sh --port /dev/ttyUSB0

Build and flash ESP32-S3:

./scripts/flash-esp32-s3.sh --port /dev/ttyACM0

Use COM4-style ports on Windows and /dev/cu.* ports on macOS.

Device Setup

On first boot, the device starts an open setup Wi-Fi network named like m-ABCD. Join that network and open the shown address, usually 10.x.x.1. The setup page scans for nearby Wi-Fi networks, tests the selected credentials, saves them, and reboots.

After the device joins your Wi-Fi, open the IP shown on the display. The web UI serves:

• / or /stats: live hashrate, pool, share, payout, memory, and build data.
• /settings: display, performance, pool, wallet, reboot, and factory reset.
• /wifi: change Wi-Fi after setup.
• /licenses: bundled license texts and notices.
• /health: plain ok health check.

The BOOT button advances display pages. Hold BOOT for 5 seconds at startup or while running to factory reset settings.

More device-use details are in Device usage.

Development Notes

• User-facing shell commands live in scripts.
• Web UI source lives in web/ and is embedded during the CMake build.
• Firmware source lives in src/; large modules are split into .inc files and registered as object dependencies in src/CMakeLists.txt.
• Release builds create merged flash images for OLED and LCD variants, attach them to GitHub releases, and update the GitHub Pages flasher manifest.
• TLS is disabled in the current sdkconfig to reduce memory pressure. See TLS support notes for design work if TLS Stratum support is revisited.

Useful development builds:

./scripts/build-firmware.sh --synthetic
./scripts/build-firmware.sh --test-block-found
./scripts/build-firmware.sh --ideaspark-19-lcd --lcd-debug-dirty-rects

License

Project-owned firmware, scripts, web UI, and documentation are MIT licensed. See LICENSE, ATTRIBUTION.md, and THIRD_PARTY_NOTICES.md.