Replace MEGA with cheaper microcontroller

Projects General Guidance
1

Hello. Recently I was able to take an Arduino MEGA home, and I found a use for it.

The volume controls on my keyboard are annoying, so I plugged a potentiometer and an LED right into the Arduino, then I made an Arduino script that writes the potentiometer to the serial monitor. Then I wrote a python script that reads the serial monitor and changes my PC volume to match it. The LED also dims based on the serial monitor value.

Here's the thing. I might want to use the MEGA on something else. So, I want to buy a really cheap microcontroller that has an analog port, at least one digital port, and can talk with the computer over the serial monitor. The three chips I found are Arduino Nano, ESP8266, and ESP32. But I wanted to ask someone before I throw money at one.

Do you have any recommendations?

2

All the alternative you mention work - neither the Nano or ESP8266 or ESP32 have a great Analog Input (ADC component) but for what you describe it should be enough

you can find really cheap boards esp. if you are not in a rush and you buy from the Far East ...

3

That's good to know, thanks. Could you give any specific names of some knockoff boards or just somewhere to start looking?

4

The official Arduino store even if you buy clones later. I'd suggest a Micro or Nano.

1 Like
5

The cheapest, and smallest, controller you'll find to do this is probably the Seeed XIAO RP2040.
I think it was about 5US$ last time I got some.

Be careful with some of the smaller versions of "arduinos" like the micro, pro micro, nano etc, some of them can be tricky to flash.

6

Suggest looking into using the HID/keyboard emulation capabilities of a Pro Micro.

1 Like
7

I would suggest the Nano, I have been using them for years and generally treat them like a through hole IC and simply plug it into my project that is a custom PCB. I usually put a 0.1 uF MLCC cap on Vref, that appears to stabilize the A/D.

1 Like
8

I am agree with @gilshultz and I’ll add that the Nano clone on Ali is one of the cheapest Arduinos - it costs less than $2

9

My advise would be to stick to AVR based boards (Nano, Micro, Pro Micro); the only thing you might have to adjust is the PWM pin but further it will be straight forward.

When using a board that can act as a HID (Micro or Pro Micro and lots of others), you might be able to get rid of the python script.

1 Like
10

My vote would be for a Pro Micro. Not expensive, a decent ADC and can act as an HID - so you may be able to provide more functions than just a volume control.

11

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.