Battery, MuPiHAT and power button
Under Settings › Battery & Power you find everything about the power supply
Under Settings › Battery & Power you find everything about the power supply.
Battery display
Settings › Battery & Power › Battery shows the charge level, the voltage and the history of the last 24 hours. The display shows the level in the status indicator.
While charging, the voltage reads too high, because the charger lifts the battery above its rest voltage. So while charging the box counts the charge that goes in, starting from the level before the cable was plugged in, and shows full in about …. Shortly after charging, while the voltage is still raised, it keeps counting, and only then goes by the voltage again. The time is an estimate: if the box plays at the same time, the battery gets less current, and a weak 5 V power supply charges it much more slowly.
MuPiHAT and battery profile
The MuPiHAT is a board with battery management that is plugged onto the Raspberry Pi. Under MuPiHAT & battery profile you set:
| Setting | Meaning |
|---|---|
| MuPiHAT active | switches the support on. Switching it also changes the sound card and restarts the box |
| Battery | the profile of your battery: Ansmann 2S1P, ENERpower 2S2P 10.000mAh, ENERpower 2S3P 15.000mAh, USB-C operation (without battery) or Custom profile |
Below it are the voltages of the chosen profile in millivolts. You can change them and apply them with Save profile; the MuPiHAT service restarts for this. If none of the profiles fits your battery, choose Custom profile. With USB-C operation (without battery) there are no voltages and no charge curve.
| Card | Value | Range |
|---|---|---|
| Charge curve | Empty, 25 %, 50 %, 75 %, Full (v_0 to v_100): the voltage at this charge level. The values rise from “Empty” to “Full” | 5000–9000 each |
| Thresholds | Warning from: from this voltage the box warns | 5500–8000 |
| Thresholds | Shut down at: from this voltage the box switches itself off. Must be below the warning | 5000–7500 |
| Charging | Charge cutoff (VREG, optional): the voltage at which charging ends. Empty = the charger chip's default | 6000–8400 |
| Charging | Capacity (mAh, optional): the size of the battery, for the time until full. Empty = the size from the profile's name | 500–200000 |
If the battery is empty, the box switches itself off, and the display first shows the “battery empty” picture (Covers and themes). With Telegram you also get a message when the battery is almost empty (Telegram).
Automatic shutdown
Settings › Battery & Power › Automatic shutdown: The box switches itself off when nobody is listening. Adjustable from 0 to 300 minutes in steps of five. 0 means never, that is how it is set after installation. The box checks every 10 seconds whether something is playing.
Power button and LED
With an OnOff SHIM (on/off button with status LED) you switch the box on and off cleanly. Under Power switch and LED:
| Setting | Effect |
|---|---|
| Delay of the shutdown button | how long you hold the button until the box goes off, 0 to 5 seconds (2 after installation). Applies after a restart |
| LED pin (OnOffShim) | the GPIO pin of the LED (13 after installation). Applies after a restart |
| LED brightness normal | brightness in operation, 0 to 100 % |
| LED brightness dimmed | brightness when dimmed, 0 to 100 % |
When switching off, the display shows the goodbye picture, a sound plays, and the LED fades out slowly. If music is playing, it is paused first.
If the box hangs when switching off and does not go off, read The box hangs when shutting down.