I'm doing a project for my institution where there are 4 main building blocks with 4 electric bells inside these buildings. These are worked using a switch so the bells ring with delay and not at the correct times. But there is the same internet connection going across all the buildings. So, my idea here is to implement a system for the bell by fetching the real-time from the web and should be able to program this to a microcontroller ic to specify on which times the bell should ring and by that, we can implement the same system to all 4 buildings and they will ring at the exact time without any delay and synchronized also. I can only use any microcontroller ICs and can't use any kind of development boards. The basic functioning of the system should be this. The other features that can be added are a manual button to ring the bell and access the bell via a phone or computer with a simple and very basic interface where we can activate the using that device and should be able to schedule the dates this bell should ring and on other days the shouldn't ring. I can only use microcontroller ICs only cant use any type of development boards, So I need to know about which microcontroller I can use for this project. This project should be budget-friendly, and all the pins of the microcontroller should be utilized if possible also suggest a wifi module compatible with the microcontroller.
what do you mean by that?
for example, I can use atmega328p, and attiny85 like microcontroller ICs but can't use any Arduino uno or other development boards like that.
For a bare bones project( no development board) with wifi.
I suggest a ESP8266 IC as it is easy to use and has wifi built in.
OK - weird constraint.
do you have electronics / PCB design and C++ programming skills?
Its for the project for the campus thats why these types of constraints.I have some sort of basic level of knowledge is there if needed im ready to learn about new things.
you'd probably be better off to prototype using development boards and when everything works well then move to your own PCB design.
But i have no idea no idea which would be most suitable microcontroller for the project, I thinked about using atmega328p but they have 28 pins and dont know does it utilise all the pins and is there any cheap and better alternative than that.
the MCU is not going to be the main cost driver if you have to build your own PCB and enclosure.
if you plan to install that in a public place (schools and colleges) you'll have regulations and certifications to follow + installation cost....
WiFi or Ethernet?
You are going to need something that has network capabilities, and possibly bluetooth for the cell phone connection. ESP32 or ESP8266 would be the likely choice, but if you want to get down to building the entire board from components you will need someone with considerable design experience.
both can be used but for prototyping wifi would be better i think also for showcasing the prototype there is no need of implementing the system to the 250v electric bell instead a buzzer can be used
for showcasing I would use some ESP32
there are really small ones with few pins like the XIAO ESP32C3 or more complete ones with builtin lcd...
you'll need to decide how you'll drive the bells which will require some electronics - but indeed could be a simple buzzer for the showcase
please continue on with the system description. How do you power the devices 24/7 and ensure they are all working? How do you control a bell? Are they AC or DC operated bells? How much current? How many bells per Arduino?
only need to work from morning around 9am to evening 5pm and around 5 6 days weekly on holidays and other time there is no need to ring the bell they are 250v electric bells mainly there are around 4-5 bells each buildings have 1 bells now they are not synced and not ringing at the same times
So your Arduino can be turned off, except when needed, is that what I read?
yeah like that or in a auto sleep mode
How much time do you have to do all this?
around 1 and a half month
Why does this sound like a school project aka homework?
For prototyping and showcasing your class project, start with any ESP32 module, and use an LED to represent the bell.