Consultation on related issues

1. Can you explain item 4 in detail? The resistors and soldering positions used by 5V MCU, and the resistors and soldering positions used by 3.3V MCU, I am a bit confused.
2. How to charge the battery?
   

[nendezkombet]

hi, if you used 3.3v MCU you need 10ohm resistor and 22ohm resistor and look at the bottom legend like in the picture above there are two resistor for TRS jack midi connection "the left side for 10ohm resistor and 22ohm resistor for the right side" resistor do not have polarity so just solder them, If you used 5v MCU just replace them with 2x 220ohm resistor.

For battery you need detach the battery from controller and charge with charging module like TP4056 or other variant. if i have a time i will upgrade this project including onboard charging module and midi input features.

Thank you very much for your answer

I use a 5V MCU to upload the program at the same time, but there is no response to the BUTTON1 operation, there is no problem with the line, I don’t know why

027222d1cd651eba43c5dfd7e156df30.mp4

[nendezkombet]

did you mean you use other arduino like nano or uno to upload the sketch to 3.3v promini ? make sure you connect VCC pin on promini to 3.3v on the uno/nano. Than in the IDE select promini with 8Mhz 3.3v varian and upload the sketch.

It's weird if the first button doesn't work, if you have multimeter you can check the switch connection maybe defected switch and try desolder and replace with spare switch you own.

other possibility the bad solder joint from MCU so the button line does not actualy connected.

I am using a 5V promini, and there is no problem with the multimeter test switch and the circuit. It is very strange. Also, is the LED of button 1 on by default after the power is turned on?

[nendezkombet]

hi sorry for my poor project documented, i see your video the programmer still connected to promini, first button used pin13 on promini that used for ISP programer when it's connected and onboard blink led, it's normal if those button doesn't work when all promini breakout connected to uploader, so try detach the programer and power the mcu with external power supply at least 7v minimum or use 9v battery pack connected to battery breakout pin. Alternatively keep connection between promini and programmer except MOSI,MISO,SCK and DTR pin. I mean use VCC and GND just for powering promini (just for testing purpose) normaly the first button will work and try sending MIDI data via TRS and MIDI cable to your hardware like guitar FX/Synthesizer.

I explained before , promini just for hardware controller and external power supply, if you want software controller use promicro that support native usb.

Well, I thought of this reason too, but I haven't had time to test it because I don't have a proper power supply, thanks again!

After my test, I found that the problem of connecting VCC and GND power supply or 9V battery power supply still exists.

[nendezkombet]

it's weird, mine working well. Maybe the connection between switch to MCU or MCU breakout to the chip controller.

The promini onboard LED responds when button 1 is operated

[nendezkombet]

when button1 pressed do actualy sending data? and check the sketch one more time if you miss something!