Testing status
A checklist of what has and hasn't been tested on real hardware. The first hub prototype was
built from commit 1645733. The
current design files include fixes for problems found on it, and that revision has not been
built yet.
| Status | Meaning |
|---|---|
| Tested | Worked on the prototype. |
| Issue, fixed in design | Failed or misbehaved on the prototype. The fix is in the current files but has not been tested on a board. |
| Issue | Misbehaves, with no fix yet. |
| Not yet tested | No result yet. |
Features not listed here have not been tested.
Last updated 2026-10-13 (copy bundled with the site).Power and charging
Feature Status Notes Power from USB-C Tested DC / solar input Not yet tested Source selection between USB-C and DC Not yet tested Solar MPPT Not yet tested Charging a battery Tested Reached fast charge from USB at about 470 mA with no thermistor fitted and ts_ignore: true set. Without that setting the charger suspends charging by default.Charger status LED Tested Blinks while charging is suspended. Too bright, so the series resistor was raised in the current design (untested). Charger and input readings in Home Assistant Tested Input source, input voltage and fault status. Reverse-polarity protection Issue, fixed in design On the prototype the protection FETs were mounted the wrong way round, so their body diodes would conduct on a reversed input. The current design turns them around. Do not connect a reversed supply to the prototype. 3.3 V system rail Tested Switched user rail Tested Toggling it from Home Assistant powers the STEMMA QT port's device on and off. Power Cycle Board (Home Assistant button) Tested Ship mode, and waking with SW3Tested Works on battery power alone. With USB connected it does nothing, as the charger ignores it while an adapter is present. A brief tap of SW3 does not wake the board; holding it does.SW3 held about 10 s to hard power-cycleTested The board dropped off the API and reconnected. Running on battery alone Not yet tested Board keeps running with USB unplugged; battery current and time to empty look sensible. End of charge Tested Charging stopped with "Charge terminated" at about 4.19 V, "Battery Fully Charged" turned on, and the gauge reported 100%. Charge current setting Not yet tested Measured current follows "Charge Current Limit". Check board temperature at higher currents. Input current limit Not yet tested A low "Input Current Limit" caps the input current while charging. Charger shutdown mode Not yet tested On battery only, "Charger Shutdown" turns the board off and plugging in USB wakes it. Charger temperature and thermal regulation Not yet tested "Charger Temperature" reads sensibly while charging. Enable USB / Enable Solar Input switches Not yet tested Turning one off drops the board to the other source or the battery. Charger HIZ mode Not yet tested The input stops supplying the board. Charger status LED switch Not yet tested "Enable Charger Status LED" off turns the LED dark. Reset Charger Registers Not yet tested The firmware restores its settings afterwards, including the charge voltage limit and the ship-FET setting. Charger interrupt ( CHG_INT)Not yet tested "Charger Interrupt" fires when USB is plugged or unplugged. Fuel gauge
Feature Status Notes Battery voltage and level Tested With a battery connected, after a driver fix for the state-of-charge reading. Operation with no battery Issue, fixed in design The gauge blocked the internal I2C bus. It is now powered from the system rail. Current-sense filter Not yet tested Added in the current design. Temperature reading Issue Reads implausibly cold without a thermistor on its connector. Learned capacity and calibration Not yet tested Run the current and board offset calibrations with the pack at rest, and compare the gauge's battery current with the charger's. Thermistors on J302 and J401Not yet tested Both temperatures read sensibly, charging works with ts_ignore off, and the gauge stops reporting "Charge inhibited".Fuel-gauge alert ( FG_ALERT)Not yet tested An alert such as low charge fires, and can wake the board from deep sleep. Connectivity and programming
Feature Status Notes Flashing over the native USB port Issue, fixed in design Failed until the charger's USB data-line links were removed. They are now unpopulated by default. Boot-mode and reset buttons Tested Used to enter download mode for the first flash. Debug UART header Not yet tested ESPHome, Wi-Fi and Home Assistant Tested Over-the-air updates Tested Internal I2C bus ( J6)Tested Charger and gauge, and devices on the STEMMA QT port. User I2C bus ( J203)Tested Devices on the STEMMA QT port. Differential I2C jacks ( J201, J202)Tested Both jacks work with SparkFun QwiicBus EndPoint modules and the I2C devices attached to them. SunSprout Satellite board Not yet tested The PCB is fabricated but not yet assembled. The same pattern has been tested with the off-the-shelf EndPoint it is based on. Deep sleep and wake Tested Sleep current has not been measured. Deep sleep current Not yet tested Battery current while asleep. Status LED Issue, fixed in design Too bright, so the series resistor was raised (untested). Expansion headers ( J7, J8)Not yet tested Unfitted by default. Check a GPIO and the 3.3 V pins once fitted. VCC_2 injection (J2)Not yet tested Cut JP2/JP3, inject through J2, and confirm it reaches the far end of the cable.Wi-Fi range on the external antenna Not yet tested Signal at the real install distance.