8.8 inch 11.26 inch Screen USB/BT Keyboard RPI

5.4V 5A output test, because the 5A current produces a voltage drop on the USB test line, and there is still 5.1V on the instrument.
Welded the newly arrived 10K B3950 NTC resistor to the PCB and attached it to two batteries to monitor the battery temperature.

The keyboard PCB and case have been modified, and a 0.99-inch 40x160 LCD screen has been added. The battery voltage/temperature/chip temperature/charging current/discharging current are initially displayed. The battery capacity function needs to be further added. These are all tests on a single 10000mAh battery, and two batteries have not been connected in parallel. This may be a task that needs to be considered for safety.

The case was designed for a 9" mini keyboard and 8.8" strip display, and was printed and sprayed with industrial yellow paint. Found a suitable 10000mAh battery that can be installed in 2 pieces at the back of the keyboard with a total capacity of 20000mAh inside the case. The next step is to integrate the keyboard PCB and battery PCB and modify the shell to add a rotatable bracket.

We can get a key core after removing the casing of the USB keyboard. Now the keyboard PCB code is basically completed. The USB/Bluetooth mode can work for a long time. Bluetooth can enter sleep mode if there is no input for 1 minute,
 and it will wake up after pressing any key. But now there is a problem with Fn+Mute/Vol-/Vol+. It cannot be recognized on the PC. It can control mute/volume down/volume up on the Raspberry in USB mode but not in Bluetooth mode.