Need help in Alarm system PCB development

It was exceeding at a point when i used multiple variables. But in this case it shouldn't.If there was memory issue then the compiler gonna show it??right

Designing three different PCBs is an ambitious project for a newbie.

I would first spend a few weeks learning how to use EasyEDA.

Only to an extent. The compiler can only warn against fixed memory allocation. This is why you generally get passed warnings if your memory use exceeds something like 80%, because at that point, dynamic memory allocation may or may not exceed the remaining 20% and the compiler generally cannot warn against this. It depends on how these libraries work 'under the hood'. Display/OLED libraries are often a bit challenging on ligthweight platforms like a Nano.

Should i use other boards like esp for the display point ??Suggest some boards i can use and that can handle the programs that i am going to run.

You are right and this is what i am doing.
I am trying to be familiar with these tools.
I have worked on projects before but never got to the pcb designing and allso they were less complex than this.

Just a detail, no one apparently noticed the switch.
There are good practices in general. If you don't follow them, your project will still work most of the time, but you should always debounce switches.
Add a pull-up resistor.

https://docs.arduino.cc/built-in-examples/digital/Debounce/

For clarity, schematic components should have their inputs on the left and their outputs on the right side of the symbol—left-to-right, input-to-output flow.

If not possible, use net names (best practice).

Won't it work if i just change the code to detect the presses if there is a new press made with in a desired time and to ignore the multiple unintended presses detected??I mean is it same or not. Just asking out of curiosity.

Again, it will work as you say.
But, if your design includes the footprint, will it rise the cost of the board? No. Then, why not add the footprint? Later you can decide if adding the resistor or not.

Adding test points also is free.

I see no caps at the power supply pin for every IC.

Got you.I will edit my schematics as suggested by you.

Yes. You don't need external pullups or debounce components. Keep in mind they're not the same; this was not made very clear by the poster who suggested them. Internal pullups and software debounce work just fine; lots of commercial equipment does it the same way.

If this turns out to be a memory problem then that would be an easy option. For anything that's supposed to do graphics on an OLED I'd forego the Nano anyway and use something more powerful. ESP32 would be fine. Note that this would also eliminate the logic level converter for the radio module.

Yes. You don't need external pullups or debounce components. Keep in mind they're not the same; this was not made very clear by the poster who suggested them. Internal pullups and software debounce work just fine; lots of commercial equipment does it the same way.

If this turns out to be a memory problem then that would be an easy option. For anything that's supposed to do graphics on an OLED I'd forego the Nano anyway and use something more powerful. ESP32 would be fine. Note that this would also eliminate the logic level converter for the radio module.

Also, why did you register a new account? It's a bit confusing.

Does this also eliminate the use of external power supply for rfm module.
What will be the limitation of the current i can draw from esp?
Will I still need the voltage converter for oled ? Or maybe it would work just fine with the 3.3V as most oled supports 3-5V if I am not wrong.

I did it by mistake. I was not aware that i am using another account.

This depends on the board you select. Most ESP boars use something like an LT1117 or similar. Generally this should be adequate to also power your radio module, especially as long as you don't also use WiFi on the ESP.
But the definitive answer depends on the definitive choice of components and what you're going to do with them. There's no default answer beyond a "probably, yes".

Most OLED controllers AFAIK are natively 3.3V logic devices. I guess many accept 5V logic input for compatibility purposes. I expect most hobby OLED modules to support 3.3V logic inputs.


These are things i am gonna order.
Currenlty the circuit i am using has followings
Nano
RFM95W(9-12 RST,NSS,MoSi,MiSo--D2 intrupt D13 SCK) (3.3V nano GND nano)
7.4V POWER SUPPLY(to vin pin)
Buzzer connected to D7 and GND
Push button connected to D3 and GND
And the oled connected to a4 a5 vcc(5v) and gnd

Do i need anything extra ?
(Except logic converters)

Probably OK, assuming you're using a buzzer module that accepts a logic input.

You can't delete your own forum account AFAIK. It doesn't matter; I've already reported the post and an administrator will step in if necessary. Note that you can always alert moderators using the little flag icon at the bottom of each post and then explain what's the matter. This is the correct way of dealing with such things, which also prevents you from being sent on some kind of wild goose hunt by someone who doesn't know how this works.

Do i need to add anything more or i am good to go with the current order??(refering to the image attached in the previous message)

Will i be banned?? I was really not knowing if i have an account already.

I can't decide for you what you need to order. The items you listed look sensible, apart from the breadboard power supply module, which I never really saw the use of. Then again, it can be convenient for breadboard testing as long as power requirements are very limited. They are in your project, so far, so if you think the module will be useful, you could include it.

What I cannot judge at this point is whether you should order the parts for the other sub-systems of your alarm system, what parts you may already have on stock etc.

The ceramic capacitors are nice to keep around but not really very necessary if you're using modules, since those modules already have them onboard. It doesn't hurt to add another capacitor here and there, but in all honesty, it doesn't do much either in the kind of setup you're working on.

I don't expect so; just ignore all that nonsense. As said, these matters should be handled with the report function at the bottom of a post. Explain what needs to be done and moderators will see if they can help. They generally are forgiving of honest mistakes in my experience.

The over all summary would be as follows

  1. I am using esp32 so logic converters not required
  2. I included the power supply module AMS1117 800mA is enough to power different components seperately.
  3. Capacitors are not that much necessary but its never bad to add these to the setup.
  4. Breadboard power supply might not be necessary but it is convenient. I can use my 12v adapter directly with this to power multiple circuits.

After all these changes i am good to go right?

One of the last problem is the antenna connectors
Do i just need to connect the antenna connector(co-axial cable in my case) to the ant pin or its shield also needs to be grounded?


This is how my system looks like currently.
I am not malicious i am actually working on this project and want to develop product and i needed help in order to perfect the prototype and move to pcb development so that there will be reliability in the system.

Within limitations. The breadboard power supply you selected has a few linear regulators onboard. If you use that to make 5V or 3.3V for an ESP board, it'll work up to the point where you decide you do want to use WiFi for some reason. This will bump current draw to up to 500mA or so on the 3.3V line. With a 12V input, a linear regulator would then start to burn a couple of Watts, which it cannot handle. So you're better off with some kind of buck converter, which will be much more efficient. Maybe there are breadboard supplies with buck converters as well, these days. You'd have to shop around.

The shield needs to be grounded.

Hey I got th3 esp 32 today and the oled was working fine with the esp32
But now one more module is showing initialization failure. I don't know if its du3 to code or something else.please help me.

#include <LoRa.h>

// Define LoRa module pins
#define RFM95_CS 5     // Chip select pin (NSS)
#define RFM95_RST 14   // Reset pin
#define RFM95_INT 26   // Interrupt pin (DIO0)

// Define the onboard LED pin
#define LED_BUILTIN 2 // Change this if your onboard LED is on a different pin

void setup() {
  Serial.begin(115200); // Start the Serial communication
  while (!Serial);       // Wait for Serial to initialize

  pinMode(RFM95_RST, OUTPUT);
  digitalWrite(RFM95_RST, HIGH);
  delay(10);
  digitalWrite(RFM95_RST, LOW);
  delay(10);
  digitalWrite(RFM95_RST, HIGH);
  delay(10);

  // Initialize LED pin
  pinMode(LED_BUILTIN, OUTPUT);
  digitalWrite(LED_BUILTIN, LOW); // Ensure the LED is off

  // Start LoRa at 915 MHz
  if (!LoRa.begin(915E6)) {
    Serial.println("LoRa Init Failed!");
    while (1); // Stop here if initialization fails
  }

  Serial.println("LoRa Initialized!");
}

void loop() {
  // Send a test message
  Serial.println("Sending packet...");

  LoRa.beginPacket(); // Start the packet
  LoRa.print("Hello, LoRa!"); // Write the message to the packet
  LoRa.endPacket(); // Finish the packet

  // Indicate message sent with LED
  digitalWrite(LED_BUILTIN, HIGH); // Turn the LED on
  delay(100); // Keep it on for a short moment
  digitalWrite(LED_BUILTIN, LOW); // Turn the LED off

  Serial.println("Packet Sent!");
  delay(2000); // Wait before sending the next message
}

Module is not initialising...do i need to change the module??
Or the issue iswith power supply.

7.4V power supply to vin gnd