Arduino UNO and Raspberry Pi

Question

I have got an Arduino UNO which I have purchased recently and a Raspberry Pi which I have been using for quite sometime now. I have got a ESP8266 NodeMCU AI-THINKER dev board as well.

I have used the GPIO module to make some simple stuffs using Raspberry. Can someone tell me where to use Raspberry Pi and when to use Arduino UNO.

Will Raspberry be used as a controller and Arduino be used as a device which triggers the end devices (Arduino UNO is cost effective to become a receiving client.)

Answer 1

The answer lies within the pros and cons of the devices and weather they meet the goals of your project.

Raspberry Pi pros

• More powerful/faster - good if you have a project that requires intense computation.
• Fully fledged operating system - good if you have a project that requires more complex actions/interactions with systems or you need to make use of some of the vast amount of software available for arm linux.
• More features - if you need to make use of the extra features such as HDMI, USB host, GPU, more memory etc...

Arduino pros

• Cheaper - if cost is a concern Arduino based solutions can be a fraction of the price (the ATmega328P chip is only $1-2).
• Less power hungry - if power is a concern (running of battery) the Arduino can use a fraction of the power that the Raspberry Pi uses (> 0.2mA vs > 2-300mA for the Pi) allowing you to run for longer.
• Truly real-time - the Arduino is a real time device, if you require precise timing the raspberry Pi might not be accurate enough. This is due to it running a fully fledged non real time OS. Where as the Arduino you have complete control over the software and timing inside it.
• Reading analog sensors - the Arduino has a native ADC, the Pi does not. You can get around this in the Pi with external hardware (including using an Arduino).
• 5 V tolerant - the Arduino can talk to 5 V devices where the raspberry Pi is only 3.3 V tolerant. In most cases the Arduino can also talk to 3.3 V devices (if they are at least 5 V tolerant or read only devices) so you have more flexibility but both can make use of logic level shifters at the cost of more hardware.
• Simpler - you don't have to worry about an operating system, burning to SD cards, setting up software on the device - you just write a sketch and flash it to the Arduino.

If none of these are a concern/needed for your project then either the Pi or Arduino should work. You might find one more fiddly to used then the other for various projects but you will find that for allot of projects both will work equally well. Quite often you can take advantage of both systems in a projects; such as the real time nature of the Arduino and the software on the Pi by making the Pi talk to the Arduino over serial, SPI, I2C or another communication protocol they share.