Choice of Microcontroller Fot the Rest of Assignment and Final Project

i have selected the esp-wrom-32 MCU for the rest of assignment including this week assignment so, i started the PCB design from scratch so that that i have baseline of my future work.

Why ESP32?

The following table that provides more detail on the performance of the ESP-WROOM-32:

The ESP-WROOM-32 is a powerful and versatile chip that can support a wide range of embedded programming applications. Its dual-core processor, ample memory, and support for multiple communication protocols make it well-suited for IoT devices, while its low-power features and advanced peripheral capabilities allow for efficient and flexible design options.

In my final project, i will be using sensors and actuators that need wifi communication and I2C pins for working. that is the reason why i shifted to esp-wrom-32 Soc Chip

Circuit and PCB Design For Selected Mcu

i designed my circuit in kicad as i did in the week 7 assignment

Circuit Description

The following is The pcb routing

Finally i saved the pcb as png file then i used This toolto generate toolpath and G-code for the roland srm-20 milling machine that we use in fablab Rwanda

The final pcb have been milled and i started soldering components on the PCB

Soldering and Testing the Final PCB

Actually Soldering smd components seems to be complicated for me but i tried and i m getting familliar with it .

The esp-wrom-32 is 3.6 voltage operated so i have to use programmer that produce pick voltage that cannot go beyond 3.6volts . The folllowing image shows the usb to uart programmer that i used to flash code in esp-wrom-32 flash memory.

This is the way i connected my esp-wrom-32 to usb to uart bridge to be able to fire the MCU.

Programming and Connecting the Output Device.

in my circuit, the I/O PIN number 26 is connected to an LED . so i have to make an arduino program to turn it on/off. luckily, the ESP-WROM-32 IS SHIPPED WITH BOOTLOADER INSTALLED. it is not necessary to install bootlader unless it is not installed or modified.

Steps to program esp-wrom-32

here are the steps to program the ESP-WROOM-32 with a USB to UART module using the Arduino IDE:

1. Connect the ESP-WROOM-32 to the USB to UART module as follows:
• Connect ESP-WROOM-32 3V3 pin to USB to UART module 3V3 pin
• ESP-WROOM-32 GND pin to USB to UART module GND pin
• ESP-WROOM-32 TX pin to USB to UART module RX pin
• ESP-WROOM-32 RX pin to USB to UART module TX pin
• ESP-WROOM-32 EN pin to USB to UART module RTS pin for reset
• ESP-WROOM-32 IO0 pin to USB to UART module DTR pin for boot mode

2. Download and install the Arduino IDE if you haven't already done so.
3. Open the Arduino IDE and go to "File" -> "Preferences". In the "Additional Boards Manager URLs" field, enter the following URL:

    
        https://dl.espressif.com/dl/package_esp32_index.json

    

4. Go to "Tools" -> "Board" -> "Boards Manager". Search for "esp32" and install the "esp32" package by Espressif Systems.
5. Go to "Tools" -> "Board" and select "ESP32 Dev Module".
6. Go to "Tools" -> "Port" and select the port that corresponds to the USB to UART module.
7. Open the "Blink" example sketch by going to "File" -> "Examples" -> "01.Basics" -> "Blink".
8. n the sketch, change the LED pin number corresponding to what you have LED attached to. in my case is 26
9. Verify the sketch by clicking on the "Verify" button (checkmark icon).
10. Upload the sketch by clicking on the "Upload" button (right arrow icon).
11. Push on the boot button when ready to upload
12. If the upload is successful, the LED on the ESP-WROOM-32 should start blinking.

here is an Arduino code that will turn on the buzzer and LED on the ESP32 Dev Module for 1 second and then turn them off for 1 second, respectively:

    
        // Pin Definitions
        const int BUZZER_PIN = 25;
        const int LED_PIN = 26;
        
        // Setup function
        void setup() {
          // Initialize the buzzer and LED pins
          pinMode(BUZZER_PIN, OUTPUT);
          pinMode(LED_PIN, OUTPUT);
        }
        
        // Loop function
        void loop() {
          // Turn on the buzzer and LED
          digitalWrite(BUZZER_PIN, HIGH);
          digitalWrite(LED_PIN, HIGH);
          delay(1000); // wait for 1 second
          
          // Turn off the buzzer and LED
          digitalWrite(BUZZER_PIN, LOW);
          digitalWrite(LED_PIN, LOW);
          delay(1000); // wait for 1 second
        }
        

    

In this code, we first define the pin numbers for the buzzer and LED as constants. In the setup() function, we set the pin modes for these pins as OUTPUT.

In the loop() function, we first turn on the buzzer and LED by setting their corresponding pins to HIGH. We then wait for 1 second using the delay() function.

After the 1 second delay, we turn off the buzzer and LED by setting their corresponding pins to LOW. We then wait for another 1 second before repeating the loop.

Results