Hey guys. I´m kinda new to all this and I dont know much about C and C++.I can edit code but I cant put it together. I hope I will learn it but now I got this idea and cant put code together. So I got this idea of making volt meter out of arduino via that voltage sensor. Basic voltage devitor with 30k resistor and 7.5k resistor. I want to measure more than 5V via analog pin so I need that.
Now is hard part... atlest for me I know you coding mages can make code like that on toilet.
So I want to mesure those data via analog pin and send it thrue bluetooth to 2nd arduino pro mini and display it on 128x32 oled (with 4 pins) using probably adafruit library. I need to autoconnect two devices.
Could you give me any sugections for code or make it? As I said I can edit it change values but when I try to add something that should work it never works.
I will use this
"DC 0-25V Standard Voltage Sensor Module"
"128x32 pixel OLED"
"Pro Mini 328 5V"
some cheap bluetooth modules they should be like HC-05 I set them to speed 9600
So in my mind is. I will start voltmeter device with probes after that I will start Oled device. They will instatly connect and when I measure for example car battery it will send data (voltage) with about 250ms delay to display. And line that will make anything under 0.1V = 0V. On display there should be 4 digits like 12.38V.
Thats all. I hope you can help me. I think its nice project for everybody and we can make it work together. Thank you.
To see how to connect 2 HC05 Bluetooth modules Google "connect 2 HC05" for lots of tutorials and videos. Then it is just a matter of reading the voltage and sending the data out the serial port that one HC05 is connected to and reading the receiver serial port and displaying the data.
Yeah my problem is with how to print on that oled after I got my analog reading thrue HC-05 to 2nd pro mini. I thing I will not get that raw analongRead from HC-05 will I. Anyway I have big problems with printing on that oled. Look at that.
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#define OLED_RESET 4
Adafruit_SSD1306 display(OLED_RESET);
#if (SSD1306_LCDHEIGHT != 32)
#endif
float R1 = 30000.0; // resistance of R1 (30K)
float R2 = 7500.0; // resistance of R2 (7,5K)
void setup() {
// Set up the display
display.begin(SSD1306_SWITCHCAPVCC, 0x3C); // Initialize with the I2C addr 0x3D if not working use 0x3C (for the 128x64)
display.setTextColor(WHITE);
}
void loop(){
// draw scrolling text
delay(250);
display.clearDisplay();
// text display tests
display.setTextSize(1);
display.setTextColor(WHITE);
display.setCursor(0,0);
display.println("Multimetr Mk.II");
display.setTextColor(WHITE, BLACK);
display.println();
display.setTextSize(2);
display.setTextSize(2);
int sensorValue = analogRead(A0);
// Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V):
float voltage = sensorValue * (5.0 / 1023.0);
float vin = sensorValue / (R2/(R1+R2));
if (vin<0.09) {
vin=0.0;
// print out the value you read:
display.print(vin); display.println("V");
display.display();
}
}
It wount print me (vin) value and I dont know why. I dont understand it much but it wont work. Its just freezed in last picture. If not its just black
Have you tried the "hello world" example that comes with the display library. That is, does the dislpay work with the simple code that just prints a hard coded message.
So I got this working look at it.
#include <Wire.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_GFX.h>
#define OLED_ADDR 0x3C
Adafruit_SSD1306 display(-1);
#if (SSD1306_LCDHEIGHT != 32)
#error("Height incorrect, please fix Adafruit_SSD1306.h!");
#endif
int analogInput = A1; // I used A1
float vout = 0.0;
float vin = 0.0;
float R1 = 9850.0; //30k
float R2 = 988.0; //7500 ohm resistor, I tweaked this
int value = 0;
void setup()
{
display.begin(SSD1306_SWITCHCAPVCC, 0x3C); // Initialize with the I2C addr 0x3D if not working use 0x3C (for the 128x64)
display.setTextColor(WHITE);
}
void loop()
{
display.clearDisplay();
// initialize and clear display
display.setTextSize(1);
display.setTextColor(WHITE);
display.setCursor(0,0);
display.println("Multimetr Mk.III");
display.setTextColor(WHITE, BLACK);
display.println();
display.setTextSize(2);
display.setTextSize(2);
// read the value at analog input
value = analogRead(analogInput);
vout = (value * 5.0) / 1024.0;
vin = vout / (R2/(R1+R2));
// display a line of text
display.print(vin,2);
display.println("V");
display.display();
delay(200);
}
It will read analong input A1 and prin it on 128x32 (A4, A5 on uno). Now I need to cut it in half like Read analog input A1 and send it to slave and slave will calculated and print it. Could you help me splice that code. I tried for like 6 hours today and nothing. Destroyed my HC-05 and nano so I waiting for new one.