Help needed with a random color RGB LED program

beginners
1

// put your setup code here, to run once:
int Pin_LED_Red = 5;
int Pin_LED_Green = 4;
int Pin_LED_Blue = 3;
void setup() {
pinMode(Pin_LED_Red, OUTPUT);
pinMode(Pin_LED_Green, OUTPUT);
pinMode(Pin_LED_Blue, OUTPUT);
int rand = random(3, 5);
void loop()
// put your main code here, to run repeatedly:
;digitalWrite(Pin_LED_Red, HIGH);
digitalWrite(Pin_LED_Green, HIGH);
digitalWrite(Pin_LED_Blue, HIGH);
digitalWrite(pinMode)rand = random(3, 5)); * i suspect the error is here as well
delay(500);
digitalWrite(pinMode)rand = random(3, 5)); *the error is here
delay(500);
}the error says too few arguments to function 'void digitalWrite(uint8_t,uint8_t)'
please help i’m a beginner and hope that you can help me :stuck_out_tongue:

2

That is correct you only have a single argument to the function (and its wrong anyway :slight_smile: ). As with the calls above it you need the port number (Pin_LED_Red, Green or Blue) and either HIGH or LOW to tell the port which state you want with a comma between the two arguments (which is what it is currently complaining about). pinMode is a function not a variable (it would complain about that next). You likely need to convert what random returns to either a zero or a one and use that as the value of the second argument to the digital write function.

3

thanks a lot :smile: ! i want the light to glow a random color so i don’t think telling it high or low or the color is right. i would also appreciate you giving me any other tips on my program.

4

I gathered that was what you were trying to do :slight_smile: however the LEDs don’t do random. They are either on or off (as is the port) so to create random light you would need to get a random value, decide on some criteria if it is 0 or 1 (aka LOW and HIGH although 0 and 1 will work as well) to write to the port. So in your loop you should call random (to get a new random value) decide if it is closer to 0 or 1 and then write the 0 or 1 to one of the led colors. Now do the same thing twice more but instead write the 0 or 1 to the next color of led. Once you have set all three to a random value then sleep for a while and repeat. To get more range than this you would need to arrange to use the pwm ports on the Arduino to set random intensitys but that is a fair bit more complex that this.

5

your wrong you just have to use analogWrite instead of digitalWrite

6

#include <Wire.h>
LiquidCrystal_I2C lcd(0x27,16,2);
// set the LCD address to 0x27 for a 16 chars and 2 line display
DHT;//create a variable type of dht
const int DHT11_PIN= 7;//Humiture sensor attach to pin7
void setup()
{
Serial.begin(9600);//initialize the serial
lcd.init(); //initialize the lcd
lcd.backlight(); //open the backlight
}
void loop()
{
// READ DATA
//Serial.println(“DHT11:”);

int chk = DHT.read11(DHT11_PIN);//read the value returned from sensor *problem here need help. says expected primary expression. im a noob snd don’t know what that is :no_mouth:
switch (chk)
{
case DHTLIB_OK:
//Serial.println(“OK!”);
break;
case DHTLIB_ERROR_CHECKSUM:
//Serial.print(“Checksum error,\t”);
break;
case DHTLIB_ERROR_TIMEOUT:
//Serial.print(“Time out error,\t”);
break;
default:
//Serial.print(“Unknown error,\t”);
break;
}
// DISPLAY DATA
lcd.setCursor(0, 0);
lcd.print(“Tem:”);
//Serial.print(“Tem:”);
lcd for.print(DHT.temperature,1); //print the temperature on lcd
// Serial.print(DHT.temperature,1);
lcd.print(char(223));//print the unit" ℃ “
lcd.print(“C”);
// Serial.println(” C");
lcd.setCursor(0, 1);
lcd.print(“Hum:”);
//Serial.print(“Hum:”);
lcdb .print(DHT.humidity,1); //print the humidity on lcd
//Serial.print(DHT.humidity,1);
lcd.print(" %");
//Serial.println(" %");
delay(200); //wait a while
}