while i read API frames in ardiuno
in Serial window i got simply
FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF,FFFFFFFF
void setup()
{
Serial.begin(9600);
}
void loop()
{
if (Serial.available()>=0){
for(int i=0;i<22;i++)
{
Serial.print(Serial.read(),HEX);
Serial.print(",");
}
Serial.println();
}
}
Plz someone give me a solution. i could not identify the problem
You're trying to read when Serial.available() indicates there isn't anything there to read, so Serial.read() is probably returning -1.
void setup()
{
Serial.begin(9600);
}
void loop()
{
if (Serial.available()>0){
Serial.println(Serial.read(),HEX);
}
}
change the line serial.available()>=0 to serial.available()>22
u will get data.
Related
I'm doing a code where the timer gets triggered by a pushbutton. The problem is that nothing happens, the serial monitor doesn't show anything. I've checked all of the connections and there is no errors in the electronic components. I'm not sure what is wrong.
Thankyou
Here's the code:
int timer;
const int starttrigger = 2;
const int endtrigger = 4;
void setup() {
pinMode(starttrigger, INPUT);
pinMode(endtrigger, INPUT);
pinMode(redled, OUTPUT);
pinMode(greenled, OUTPUT);
}
void loop() {
int start_button_state = digitalRead(starttrigger);
int end_button_state = digitalRead(endtrigger);
if (start_button_state == HIGH) {
while (end_button_state == LOW){
for(timer = 0; end_button_state == HIGH; timer ++) {
Serial.println(timer);
}
}
}
}
You do not see anything in the serial monitor because you have not activating Serial communication in the first place. It needs to be done in the void setup() function.
Please add this line to your void setup function
Serial.begin(9600);
I am using Arduino Uno, I try to run servo constantly from 0 to 45 degrees when the interrupt button is pressed it should go to -30 degree and wait here. When the same button is pressed again, it should resume the constant action, which is swiping 0 to 45 degrees without <servo.h> library.
I tried to run like this:
const int servo = 11;
const int led = 13;
const int buttonPin = 2;
volatile int buttonState = 1;
void setup() {
Serial.begin(57600);
pinMode(led, OUTPUT);
pinMode(servo, OUTPUT);
pinMode(buttonPin, INPUT_PULLUP);
attachInterrupt(digitalPinToInterrupt(buttonPin),Button,CHANGE);
}
void loop() {
digitalWrite(led,HIGH);
for(int i=0;i<30;i++)
{
digitalWrite(servo,HIGH);
delayMicroseconds(1500);
digitalWrite(servo,LOW);
delayMicroseconds(18500);
}
delay(2000);
for(int i=0;i<30;i++)
{
digitalWrite(servo,HIGH);
delayMicroseconds(1000);
digitalWrite(servo,LOW);
delayMicroseconds(19000);
}
delay(2000);
}
void Button()
{
digitalWrite(led,LOW);
for(int i=0;i<30;i++)
{
digitalWrite(servo,HIGH);
delayMicroseconds(1833);
digitalWrite(servo,LOW);
delayMicroseconds(18167);
}
}
I have no problem coding my own PWM for each case but it turns out, the problem is a bit complicated than I was expecting because when we try to resume, I need to disable the interrupt function when pressing the same an interrupt button somehow.
Is it possible in this way or is there a better way to implement it?
The objective is to enter "on" and "off" in COM port and switch the Pin 13. No matter what I do. It won't switch on or off. Need help. I tried to see if the string I entered is "on". It prints "on" but when I check for the result it shows its different. What is wrong?
String SData;
String SData1;
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
pinMode(13,OUTPUT);
digitalWrite(13,HIGH);
delay(5000);
digitalWrite(13,LOW);
delay(1000);
}
void loop() {
// put your main code here, to run repeatedly:
while(Serial.available()==0)
{
}
SData=Serial.readString();
SData1="on";
if(SData==SData1)
Serial.print("Same");
else
{
Serial.print("Different");
// Serial.print(SerialData-SerialData1);
Serial.print(".");
}
if(SData=="on")
{
digitalWrite(13,HIGH);
Serial.println("LED ON");
delay(2000);
}
Serial.println(SData);
if(SData=="off")
{
digitalWrite(13,LOW);
Serial.println("LED OFF");
delay(2000);
}
SData="";
}
I've got a problem with my arduino program. I'm using a RFID reader to scan cards (this part works flawlessly). I want the program to grant access to using some buttons (doesn't matter to be honest). The user who uses a verified card can use the functionalities until he scans a card again. I've deleted some unnecessary parts of the code.
#include <SPI.h>
#include <MFRC522.h>
String read_rfid;
String ok_rfid_1="a3f90f7"; //ID of the verified CARD
const int buzzer=8; //Buzzer
const int redLed=7;
const int greenLed=6;
const int yellowLed=5;
byte access=false; //
void setup() {
Serial.begin(9600); // Initialize serial communications with the PC
SPI.begin(); // Init SPI bus
mfrc522.PCD_Init(); // Init MFRC522 card
}
/*
* Helper routine to dump a byte array as hex values to Serial.
*/
void dump_byte_array(byte *buffer, byte bufferSize) {
read_rfid="";
for (byte i = 0; i < bufferSize; i++) {
read_rfid=read_rfid + String(buffer[i], HEX);
}
}
void granted() { } //it lights up the green led
void denied() { } //it lights up the red led
void login() {
if (read_rfid==ok_rfid_1) {
granted();
access=true;
} else {
denied();
}
delay(1000);
}
void logout() {
if (read_rfid==ok_rfid_1 && access==1) {
access=false;
Serial.println("Logout ");
}
}
void loop() {
// Look for new cards
if ( ! mfrc522.PICC_IsNewCardPresent())
return;
// Select one of the cards
if ( ! mfrc522.PICC_ReadCardSerial())
return;
dump_byte_array(mfrc522.uid.uidByte, mfrc522.uid.size);
Serial.println(read_rfid);
login();
while(access==true)
{logout();};
}
The logging in part works well, but it logs out automatically. As I observed the problem might be that if(read_rfid==ok_rfid_1 && access==1) is always true, because the read_rfid does not change. Do you have any ideas to solve my dillema?
I want to move my robot a set number of steps and then have it stop. However the loop just seems to run on infinitely. Is there a mistake in the way that I am using void loop() or perhaps in the way that I have written my 'for' loop?
// walkerForward.pde - Two servo walker. Forward.
// (c) Kimmo Karvinen & Tero Karvinen http://BotBook.com
// updated - Joe Saavedra, 2010
#include <Servo.h>
Servo frontServo;
Servo rearServo;
int centerPos = 90;
int frontRightUp = 75;
int frontLeftUp = 120;
int backRightForward = 45;
int backLeftForward = 135;
void moveForward(int steps)
{
for (int x = steps; steps > 0; steps--) {
frontServo.write(centerPos);
rearServo.write(centerPos);
delay(100);
frontServo.write(frontRightUp);
rearServo.write(backLeftForward);
delay(100);
frontServo.write(centerPos);
rearServo.write(centerPos);
delay(100);
frontServo.write(frontLeftUp);
rearServo.write(backRightForward);
delay(100);
}
}
void setup()
{
frontServo.attach(2);
rearServo.attach(3);
}
void loop()
{
moveForward(5);
}
the loop() function is executed within an infinite loop (if you check the main cpp file that ships with the Arduino IDE, you'll see something like this:
int main()
{
setup();
for (;;) {
loop();
}
return 0;
}
So either put the call to your moveForward() function to setup() and make loop() an empty function, or call exit(0); from within loop() after moveForward(). The first approach looks like this:
void setup()
{
frontServo.attach(2);
rearServo.attach(3);
moveForward(5);
}
void loop()
{
}
And the second one looks like this:
void setup()
{
frontServo.attach(2);
rearServo.attach(3);
}
void loop()
{
moveForward(5);
exit(0);
}
Since you probably will want to eventually do more than move the robot just 5 steps, I'd suggest using a variable flag to hold the robot state. It only executes the movement routine when the flag has been set to true.
If you are using serial, when a move command is received (and the number of steps, direction perhaps?) you set the flag to true and then issue the move command. If you are using sensors or buttons, the same logic applies.
You will need some logic to handle an incoming movement command while a movement is occurring (though with your tight movement loop you actually won't be able to respond to incoming commands unless you use interrupts - but you want to consider this sort of thing if you are planning to build out a full movement bit of firmware).
boolean shouldMove;
void setup()
{
shouldMove = true;//set the flag
}
void loop()
{
if (shouldMove){
moveForward(5);
}
}
void moveForward(int steps)
{
shouldMove = false; //clear the flag
for (int x = steps; steps > 0; steps--) {
// tight loop controlling movement
}
}
}