From Opentrailpaper · · 1 min
LilyGO T5S3 E-Paper: A DIY Trail Computer
A sunlight-readable e-paper board built for cycling navigation comes with impressive features alongside distinct DIY tradeoffs.
In brief
A sunlight-readable e-paper board built for cycling navigation comes with impressive features alongside distinct DIY tradeoffs. The LilyGO T5S3 offers a highly readable, open-source bike computer base, but requires custom weatherproofing and relies on estimated elevation. Originally reported by Opentrailpaper.
Readable e-paper built for trails
The LilyGO T5S3 pairs a sunlight-readable 4.7-inch e-paper display with an ESP32-S3 microcontroller, integrated USB-C, and browser-based firmware flashing.
“A 4.7" e-paper panel that is readable in direct sunlight”
Sensor connectivity and offline maps
Bluetooth 5 links directly to external heart-rate, power, and cadence sensors. An onboard SD card slot stores offline map tiles and ride logs.
“Bluetooth 5 for heart-rate, power and cadence sensors”
Basic navigation with missing sensors
Standard GPS can struggle under dense tree cover. Because the board lacks a built-in magnetometer, map screens can only orient while you are actively moving.
“Without a compass the map can only orient from your direction of travel”
Estimated climbing and eight-hour runtime
Without a barometric altimeter, total ascent is calculated from map elevation data. A 1,500 mAh battery powers the device for around 7.4 hours without the front light.
“A 1,500 mAh build ran for roughly 7.4 usable hours with the front light off.”
Touch controls require custom protection
Capacitive touch controls are difficult to operate in rain or while wearing thick gloves. The unsealed bare board requires a custom weatherproof enclosure before riding.
“The board ships bare with no seal or IP rating”
The big picture
The LilyGO T5S3 offers a highly readable, open-source bike computer base, but requires custom weatherproofing and relies on estimated elevation.
