I just read about the newest member of the raspberry pi family, the pico, at an unbelievable price of $5.24CDN (4USD I believe?)!!!
It is the first Raspberry Pi purpose built microcontroller using their own RP2040 processor. For those not familiar, a microcontroller is a small dedicated processor that runs either a C/C++ or Micro Python program and provides very fast response to changes in I/O pins, native analogue inputs, and operates at a fraction of the power consumed by it's older and larger brothers. Here is a link to the datasheet
A Pi 4 is a great device to run linux software, connect wirelessly to the web, surf the net, check your email, and while it is taking care of all of those tasks, monitor the GPIO (General Purpose Input & Output) pins to your plant watering system, or weather station and react to their changing inputs. While it can do all of those tasks, there will be delays in its response to changes with the input and therefore the output.
A microcontroller is a small dedicated computer that could monitor those inputs and modify the outputs with less delay since this is its primary job. Since it draws a fraction of the power consumed by the next largest sibling, the Pi Zero W, it is a great candidate for battery operated projects.
You need to communicate with your microcontroller through your larger computer, such as your Pi 4, laptop, or PC.To program it, you'll need to develop your software on your larger computer and then download it to the Pico. If you hold down the "BOOTSEL" button on the Pico while plugging in your MicroUSB > USB cable into your Pi4 it will appear as a USB mass storage device on your computer. You would then copy your program to it and restart it. There is a great Raspberry Pi project for getting started with the Pico and MicroPython.
I've often used Arduino Nano & Uno microcontrollers with my Raspberry Pi project when I wanted a dedicated microcomputer to monitor inputs and react quickly. I've been successful in connecting them together using USB or Serial communication. So I've placed my order and am really looking forward to playing with it once it arrives!
Thanks for viewing.
Posted with STEMGeeks