I used following code to write to digital pin with Serial.begin. Using Serial.begin affected my digital write. The correct timing will not happen.
#define led 0
void setup() {
// put your setup code here, to run once:
pinMode(led,OUTPUT);
Serial.begin (115200);
}
void loop() {
// put your main code here, to run repeatedly:
delay(500);
digitalWrite(led,LOW);
delay(500);
digitalWrite(led,HIGH);
}
I discovered that I cannot using digital pin 0 and 1 as input or output when using serial. Serial transmit(tx) and Receive (Rx) is on 1 and 0 respectively. It is shown in the Arduino Uno board. Solution was to use a different digital pin (2-13).
Related
I'm trying to send data from Arduino UNO to NodeMCU via UART.
What I want to do is that when Arduino UNO sends "on" String to the NodeMCU, NodeMCU lights up its builtin LED, when "off" - it turns off.
I send data from Arduino UNO via standard Serial.println (). On the NodeMCU I use the SoftwareSerial library. I assigned rx and tx to pins D7 and D8 accordingly. Serial ports on Arduino(standard) and NodeMCU(SoftwareSerial) are set at 9600 baud rate.
Standard Serial port (USB) of NodeMCU is set to 115200.
I send the string that I receive from the Arduino to the standard serial port of the node (connected to usb)
The question is:
On the standard port of NodeMCU, which I view through the Arduino IDE, messages coming from the arduino are displayed, and displayed correctly (those that were sent), but the NodeMCU does not want to accept them in conditional statements and light up my LED. Why?
At the same time, when I remap the virtual UART to its original pins (connected to USB, GPIO3 and GPIO1, and send the same messages via usb through the COM port view in the Arduino IDE, the LED turns on and off as I programmed it.
Do you have any ideas why this is happening?
By the way, I do not lower voltage coming from Arduino RX and TX pins from 5V to 3.3V, but since messages are recived coorectly, I don't think that this is causing a problem.
Here's my code:
Arduino:
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
}
void loop() {
// put your main code here, to run repeatedly:
Serial.println("on");
delay(1000);
Serial.println("off");
delay(1000);
}
NodeMCU:
#include <SoftwareSerial.h>
SoftwareSerial s(D7,D8);//rx,tx
void setup() {
// put your setup code here, to run once:
Serial.begin(115200);
s.begin(9600);
pinMode(D4,OUTPUT);
}
void loop() {
// put your main code here, to run repeatedly:
String str = s.readStringUntil('\n');
Serial.println(str);
if(str == "on"){
digitalWrite(D4, HIGH);
}
if(str=="off"){
digitalWrite(D4, LOW);
}
}
Screenshot of COM4:
Screenshot of COM4:
UPD: I tried using sending 1 or 0 as int value via Serial.write() and s.read() and it works, maybe the prolem is in String type somehow
You Use İt Maybe Work
#include <SoftwareSerial.h>
String text = "";
SoftwareSerial s(D7,D8);//rx,tx
void setup() {
// put your setup code here, to run once:
Serial.begin(115200);
s.begin(9600);
pinMode(D4,OUTPUT);
}
void loop() {
// put your main code here, to run repeatedly:
String str = s.readStringUntil('\n');
text = str
Serial.println(text);
if(text == "on"){
digitalWrite(D4, HIGH);
}
if(text =="off"){
digitalWrite(D4, LOW);
}
}
Hi can someone help with crating a pwm(or very similar) signal without analogwrite on the Arduino IDE because analogwrite wont work on the esp32.
And without using a library.
I need it to take values from 0 to 255.
I was thinking to use the second core one the esp32 but I have to control more than one pin.
you can create PWM pulse with delay or millis function. for example:
void setup()
{
pinMode(13, OUTPUT);
}
void loop()
{
digitalWrite(13, HIGH);
delayMicroseconds(100);
digitalWrite(13, LOW);
delayMicroseconds(1000 - 100);
}
when you change the delay value, you can change duty-cycle level!
I am having problems connecting my Esp8266-01 to my Arduino Uno. I want to be able to connect it so that it can send the below code for a microswitch to Firebase (+LLC). I am not getting any response from AT commands in the serial monitor and have tried both NL & CR as well as changing from 9600 to 115200 baud rate. My esp only displays a red led and not the blue one.
int pressSwitch = 0;
void setup()
// put your setup code here, to run once:
{
Serial.begin(9600);
}
void loop()
// put your main code here, to run repeatedly:
{
pinMode(LEVER_SWITCH_PIN,INPUT);
pressSwitch = digitalRead(LEVER_SWITCH_PIN);
if(pressSwitch == HIGH)
{
Serial.println("CLOSED");
delay(1000);
}
if(pressSwitch == LOW)
{
Serial.println("OPEN");
delay(1000);
}
}```
I have a pixicam connected to an Arduino Uno. The pixi.init() method seems to be interfering with a normal blinky program. Here is the smallest reproducable program:
#include<SPI.h>
#include<Pixy.h>
Pixy pixy;
// the setup function runs once when you press reset or power the board
void setup() {
// initialize digital pin LED_BUILTIN as an output.
pinMode(LED_BUILTIN, OUTPUT);
pixy.init();
}
// the loop function runs over and over again forever
void loop() {
digitalWrite(LED_BUILTIN, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(LED_BUILTIN, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second
}
If I comment out the pixi.init() line then the program works as normal (blinking on and off). When the line is not commented out, the light fails to blink.
I am trying to finish a small project with a moisture sensor connected to a Fio V3.
I have also attach a Xbee S1 module to Fio's socket.
I have upload the following code to Fio:
int igrasia = 7;
void setup()
{
Serial1.begin(9600);
pinMode(igrasia, INPUT_PULLUP);
}
void loop(){
int sensorVal = digitalRead(igrasia);
if (sensorVal == HIGH) {
Serial1.println("0"); // Send OK to xbee
}
else {
Serial1.println("1"); // Send NOT OK to xbee
}
delay(5000);
}
On my computer using the Xbee USB explorer I am receiving correct data on X-CTU every 5 seconds.
Zero (0) while the sensor is outside a glass of water and one (1) while the sensor is in the glass of water.
I want to read these bytes to an Arduino Uno with a LCD screen attached and an Xbee shield. For this reason I have uploaded to Uno the following code:
#include <SPI.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x38,16,2); // set the LCD address to 0x20 for a 16 chars
void setup(){
Serial.begin(9600);
//configure pin2 as an input and enable the internal pull-up resistor
// pinMode(8, INPUT_PULLUP);
pinMode(13, OUTPUT);
digitalWrite(13, LOW);
lcd.init(); // initialize the lcd
}
void loop(){
if(Serial.available())
{
char getData = Serial.read();
if (getData == '1')
{
Serial.print(getData);
digitalWrite(13, HIGH);
lcd.clear();
lcd.setCursor (0,0); // go to start of 1st line
lcd.print("ATTENTION !!!!");
lcd.setCursor (0,1); // go to start of 1st line
lcd.print("WET environment");
}
else {
Serial.print(getData);
digitalWrite(13, LOW);
lcd.clear();
lcd.setCursor (0,0); // go to start of 1st line
lcd.print("dry environment");
lcd.setCursor (0,1); // go to start of 1st line
lcd.print("all looks good!");
}
}
}
It doesn't work properly :- (
I have correct functionality for 0 and while the sensor is outside the water. LCD monitor shows "dry environment".
But as soon as I place the sensor in the water, LCD is not working as required.
Even if I leave the sensor in the water the LCD still displays "dry environment".
I tried the sensor connected directly to Uno with the LCD attached and it works!
I suppose something is wrong with the serial.read() and/or my If / loop statement on UNO.
Any suggestions or advice?
When you transmit the data, you're sending it as a String "1", "0".
On the receiver, you're testing for characters '1', '0'. Strings are terminated with a null character (/u0000), whereas characters are not. Therefore the condition is always failed. You could try transmitting and testing characters only.