Show HN: Open-Source eInk Bike Computer LilyGO T5S3 4.7" E-Paper PRO↗ ESP32-S3 · 16 MB flash · 8 MB PSRAM · 960×540 e-paper · BLE 5 Supported Strengths A 4.7" e-paper panel that is readable in direct
By Coderz Club · 2026-09-04 · Tags: ai, git
Show HN: Open-Source eInk Bike Computer
LilyGO T5S3 4.7" E-Paper PRO↗ ESP32-S3 · 16 MB flash · 8 MB PSRAM · 960×540 e-paper · BLE 5 Supported Strengths A 4.7" e-paper panel that is readable in direct sunlight An SD card slot for offline maps, routes, ride files and logs GPS, capacitive touch, a front light, battery and USB-C on one board Bluetooth 5 for heart-rate, power and cadence sensors Firmware can be installed from a desktop Chromium browser over USB Tradeoffs No pressure sensor. There s no barometric altimeter, so climbing is derived from elevation baked into the map tiles rather than measured — total ascent is an estimate. Basic GPS. The receiver works, but a modern multi-band module would lock on faster and hold a fix better under tree cover or between buildings. No magnetometer. Without a compass the map can only orient from your direction of travel, so it can t point the right way while you re stopped. Measured baseline: about eight hours. A 1,500 mAh build ran for roughly 7.4 usable hours with the front light off. Power work is ongoing, so newer builds may differ. Weak hardware buttons. Most interaction goes through the touch panel, which is fiddly with winter gloves or in the rain. No waterproofing. The board ships bare with no seal or IP rating, so it needs a case or a bag of its own before you ride it in the wet.
LilyGO T5S3 4.7" E-Paper PRO↗ ESP32-S3 · 16 MB flash · 8 MB PSRAM · 960×540 e-paper · BLE 5 Supported Strengths A 4.7" e-paper panel that is readable in direct sunlight An SD card slot for offline maps, routes, ride files and logs GPS, capacitive touch, a front light, battery and USB-C on one board Bluetooth 5 for heart-rate, power and cadence sensors Firmware can be installed from a desktop Chromium browser over USB Tradeoffs No pressure sensor. There s no barometric altimeter, so climbing is derived from elevation baked into the map tiles rather than measured — total ascent is an estimate. Basic GPS. The receiver works, but a modern multi-band module would lock on faster and hold a fix better under tree cover or between buildings. No magnetometer. Without a compass the map can only orient from your direction of travel, so it can t point the right way while you re stopped. Measured baseline: about eight hours. A 1,500 mAh build ran for roughly 7.4 usable hours with the front light off. Power work is ongoing, so newer builds may differ. Weak hardware buttons. Most interaction goes through the touch panel, which is fiddly with winter gloves or in the rain. No waterproofing. The board ships bare with no seal or IP rating, so it needs a case or a bag of its own before you ride it in the wet.