I am making an stm32 based motor speed controller for a DC motor. But I can't read PWM off my receiver and I can't make my MOSFET vary the output! I need help because now it's only on or off! I am using a RobotDyn BlackPill and an STP36NF06L Mosfet. And also I use Arduino ide with the STM board.
Code:
int Motor = PA15;
int rc = PB1;
int s;
void setup() {
pinMode(Motor, OUTPUT);
pinMode(rc, INPUT);
digitalWrite(Motor, LOW);
}
void loop() {
if(s = (map(pulseIn(rc, HIGH), 1100, 1900, 0, 255)) > 200) {
digitalWrite(Motor, HIGH);
}
else{
digitalWrite(Motor, LOW);
}
delay(10);
}
If you want to read an external PWM signal you can use a timer in input capture mode, such that one channel triggers on the rising edge and the other triggers on the falling edge then compute the period and as such the frequency and duty cycle of the incoming signal. It is well documented in the reference manual and there are various examples and even YouTube tutorials of input capture mode.
Related
I have a strange problem, I have Arduino UNO/MEGA and I need to get Gyro sensors's data and I want to see the data in the serial monitor. Seems like a simple task, I wrote a simple C program which collects data from Arduino through serial monitor I can see the data. Everything is working for few minutes and after that, it stops.
This code is supposed to calculate a distance travelled in a line using encoder (PID algorithm implemented using Gyroscope data for straight motion) after reaching desired position, machine takes a U-Turn.
It stop for a second after taking the U-Turn and then starts straight motion again. The problem I'm facing is that the gyroscope readings stop randomly while machine taking the turn. Due to this, the machine keeps rotating about that point without stopping.
#include <Wire.h>
#include <MPU6050.h>
MPU6050 mpu;
float timeStep = 0.01, yaw=0;
const int motor11=6;//LEFT MOTOR FW
const int motor12=7;//LEFT MOTOR BK
const int motor1pwm=3;
const int motor21=8;//RIGHT MOTOR FW
const int motor22=9;//RIGHT MOTOR BK
const int motor2pwm=5;
int flag1 = 0;
int thres1=120;//PWM Values
int thres2=120;
void setup()
{
Serial.begin(115200);
// Initialize MPU6050
while(!mpu.begin(MPU6050_SCALE_2000DPS, MPU6050_RANGE_2G))
{
Serial.println("Could not find a valid MPU6050 sensor, check wiring!");
delay(500);
}
mpu.calibrateGyro();
mpu.setThreshold(1);
pinMode(motor11, OUTPUT);
pinMode(motor12, OUTPUT);
pinMode(motor1pwm, OUTPUT);
pinMode(motor21, OUTPUT);
pinMode(motor22, OUTPUT);
pinMode(motor2pwm, OUTPUT);
}
void loop()
{
Vector norm=mpu.readNormalizeGyro();
yaw=yaw+norm.ZAxis*timeStep;
if(flag1 == 0){
straight();
}
if(flag1 == 2){
taketurn();
}
}
void straight()
{
digitalWrite(motor11, HIGH);
digitalWrite(motor12, LOW);
analogWrite(motor1pwm, thres1);
digitalWrite(motor21, HIGH);
digitalWrite(motor22, LOW);
analogWrite(motor2pwm, thres2);
delay(8000);
flag1 = 2;
}
void taketurn()
{
float setPoint = yaw - 500;
digitalWrite(motor11, HIGH);
digitalWrite(motor12, LOW);
analogWrite(motor1pwm, 120);
digitalWrite(motor21, LOW);
digitalWrite(motor22, LOW);
analogWrite(motor2pwm, 120);
while(true)
{
Vector norm = mpu.readNormalizeGyro();
yaw = yaw + norm.ZAxis * timeStep;
Serial.print("Turning Yaw= ");
Serial.println(yaw);
if(setPoint >= yaw) {
digitalWrite(motor11, LOW);
digitalWrite(motor12, LOW);
analogWrite(motor1pwm, thres2);
digitalWrite(motor21, LOW);
digitalWrite(motor22, LOW);
analogWrite(motor2pwm, thres1);
delay(2000);
break;
}
}
flag1 = 0;
}
The serial monitor just stops displaying the reading. This does not happen every time, and it is very random. I want to get proper and continuous data. Is it a logical problem or a board problem?
Normally a random crash would indicate possibly unhandled interrupts or memory overwrite, but looking at your code and it being an Arduino program, it's unlikely to be either. I don't see any divide ops either, so you are not dividing by zero. The two possible things I see is that a) you have a "while (true)" without exit, so surely that could get you into trouble, and b) perhaps your delay functions are called with a very large value unexpectedly, and the MCU is actually just delaying a long time.
I've been trying to measure the time that the line is high on the Arduino. It goes high, then stays high for a couple of milliseconds. Then it gets pulled low for 1us and then floats back to high. My code doesn't seem to recognise the line getting pulled low. Is 1us too fast for the interrupt? How can I slow it down?
Thank you
EDIT
My thoughts are to use an RC filter in conjunction with a diode to slow the rise time enough for the Arduino to recognise the change, but only when the change occurs from the receiving line. Is this viable? Or can I use a pulse extender chip with a diode in the same way?
#define ESC 2 //the digital pin the esc signal line is attached to
int throttlePos = 0;
volatile unsigned long timer_start;
volatile int last_interrupt_time;
volatile int pulse_time;
void setup() {
// put your setup code here, to run once:
pinMode(ESC, OUTPUT); //originally set the ESC's line to output to keep line high ready for throttle armature
digitalWrite(ESC, HIGH); //keep the pulse high due to inverted throttle pulse
Serial.begin(115200); //opens the serial port for use when testing
timer_start = 0;
attachInterrupt(digitalPinToInterrupt(ESC), calcSignal, CHANGE);
for(throttlePos = 0; throttlePos <= 1000; throttlePos += 1) //these for loops arm the ESC by emulating an inverted PWM pulse, process takes two seconds
{
digitalWrite(ESC, LOW);
delayMicroseconds(1500);
digitalWrite(ESC, HIGH);
delayMicroseconds(100);
}
for(throttlePos = 1000; throttlePos <= 2000; throttlePos += 1)
{
digitalWrite(ESC, LOW);
delayMicroseconds(1000);
digitalWrite(ESC, HIGH);
delayMicroseconds(100);
}
}
void loop() {
digitalWrite(ESC, LOW);
delayMicroseconds(1200);
digitalWrite(ESC, HIGH);
delayMicroseconds(100);
delay(19);
Serial.println(pulse_time);
}
void calcSignal()
{
//record the interrupt time so that we can tell if the receiver has a signal from the transmitter
last_interrupt_time = micros();
//if the pin has gone HIGH, record the microseconds since the Arduino started up
if(digitalRead(ESC) == HIGH)
{
timer_start = micros();
}
//otherwise, the pin has gone LOW
else
{
//only worry about this if the timer has actually started
if(timer_start != 0)
{
//record the pulse time
pulse_time = ((volatile int)micros() - timer_start);
//restart the timer
timer_start = 0;
}
}
}
1/1us is 1MHz. Given that your Arduino executes instructions at 16MHz (at best, some instructions take longer), your interrupt handler could easily be missing things. However, the interrupt should still execute, even if the interrupt condition is cleared before the interrupt finishes.
Are you using the Arduino libraries for interrupts or configuring pin change interrupts directly at the register level?
Have you verified that the pulse into the Arduino is electrically sound? Without knowing more about your circuit, it's difficult to suggest a fix.
With this code written in the Arduino IDE I used to be able to call functions based on which Infrared sensor detected an object(right, left, or both). I altered the code a little bit lately but I've continued to make sure it wasn't missing any key components which made it work in the first place. I'm not sure if it's an error in my program or hardware but now, no matter what sensor detects an object, my robot just turns slightly to the left.
//Include Servo Library
#include <Servo.h>
//Define Pins for the Sensors and LEDs
#define LsensorPin 8
#define RsensorPin 5
#define LeftTransPin 7
#define RightTransPin 6
I'm using continuous rotation servos so using 0's and 180's is how I would control them at full speed. I checked the numbers over and over but they don't seem to be the problem.
//Constants for driving servo
const int RForward = 0;
const int RBackward = 180;
const int LForward = RBackward;
const int LBackward = RForward;
const int RNeutral = 90;
const int LNeutral = 90; //0 Speed
//Name the Servos for Left and Right Motor
Servo LMotor;
Servo RMotor;
The following 2 functions, when called, transmit an infrared signal through the transmitters. I do not think this is related to the problem because the sensors still detect objects, but my robot just doesn't respond the way I want it to.
//Take Reading from Left IR Sensor
void LeftIRled(){
for(int i=0;i<=384;i++){
digitalWrite(LeftTransPin, HIGH);
delayMicroseconds(13);
digitalWrite(LeftTransPin, LOW);
delayMicroseconds(13);
}
}
//Take Reading from Right IR Sensor
void RightIRled(){
for(int i=0;i<=384;i++){
digitalWrite(RightTransPin, HIGH);
delayMicroseconds(13);
digitalWrite(RightTransPin, LOW);
delayMicroseconds(13);
}
}
These functions control the direction in which the robot moves. I've checked it many times but this could possibly be one of the problems. They basically just control the spin of each individual servo with the previously declared variables.
//Controlling Servo Directions with Functions
void Forward(){
RMotor.write(RForward);
LMotor.write(LForward);
}
void Backup(){
RMotor.write(RBackward);
LMotor.write(LBackward);
}
void Stop(){
RMotor.write(RNeutral);
LMotor.write(LNeutral);
}
void Left(){
RMotor.write(RForward);
LMotor.write(LNeutral);
}
void Right(){
RMotor.write(RNeutral);
LMotor.write(LForward);
}
//Declare INPUT and OUTPUT for each Pin connected
//to Arduino Uno and set them to LOW
void setup(){
pinMode(LeftTransPin, OUTPUT);
digitalWrite(LeftTransPin, LOW);
pinMode(RightTransPin, OUTPUT);
digitalWrite(RightTransPin, LOW);
//drive forward
LMotor.attach(9);
RMotor.attach(10);
Forward();
}
Although I can't pinpoint the problem I believe it has something to do with the loop function. It is here that I transmit the infrared signal, receive it, and then call various functions which control the movement of the robot.
void loop(){
/*Drive forward until you reach an obstacle on either the
right side, left side, or both together(something in front of
you). If the left sensor goes low, he turns right, if the right
sensor goes low, he turns left. if both turn on at the same time
he stops, backs up, and turns right till he is out of danger
*/
int lstate;
int rstate;
LeftIRled();
lstate = digitalRead(LsensorPin);
delay(50);
RightIRled();
rstate = digitalRead(RsensorPin);
delay(50);
if (lstate == LOW && rstate == LOW)
{
Stop();
delay(100);
Backup();
delay(1000);
Stop();
delay(100);
Right();
delay(500);
}
else if (lstate == LOW)
{
Stop();
delay(100);
Backup();
delay(1000);
Right();
delay(500);
}
else if (rstate == LOW)
{
Stop();
delay(100);
Backup();
delay(1000);
Left();
delay(500);
}
else
{
Forward();
}
}
Any help or advice is greatly appreciated!
I'm trying to do a project where BLUNO (Arduino UNO + BLE) will connect to an iBeacon and make use of the RSSI detected.
I've already made contact between the BLUNO and the iBeacon through the AT commands. I can get RSSI result in the Arduino IDE serial monitor when I ping it with AT commands.
My problem now is in sending those AT commands through an Arduino sketch. I know I've to use Serial Communication, but my Serial.Available function never returns more than 0.
void setup() {
pinMode(13, OUTPUT);
Serial.begin(115200);
Serial.print("+++\r\n");
Serial.print("AT+RSSI=?\r\n");
}
void loop(){
if(Serial.available()){
digitalWrite(13, HIGH);
delay(5000);
}
}
What is irritating me is that I can connect BLUNO to my iPhone and get the RSSI on the serial monitor through AT commands. But that above code doesn't work!
Any help?
I'm almost done with the whole project for now.
my mistake in the last code was the initiation part that has to be done before the AT commands. The right way is
Serial.begin(115200); //Initiate the Serial comm
Serial.print("+");
Serial.print("+");
Serial.print("+"); // Enter the AT mode
delay(500); // Slow down and wait for connection establishment
instead of
Serial.print("+++\r\n");
so yeah the rest is kind of alright. Keep in mind that this BLE thing REALLY sucks in terms of accuracy in locating a beacon. The RSSI reading keep fluctuating and the calculated distance using the simplified equation here somewhere on Stack overflow is REALLY unreliable.
So yeah keep that in mind yo!
Here's my full code just for reference.
// while the AT connection is active, the serial port between the pc and the arduino is occuipied.
// You can manipluate the data on arduino, but to display on the serial monitor you need to exit the AT mode
char Data[100];
char RAW[3];
int INDEX;
char Value = '-';
void setup() {
pinMode(13, OUTPUT); // This the onboard LED
pinMode(8, OUTPUT); // This is connected to the buzzer
Serial.begin(115200); //Initiate the Serial comm
Serial.print("+");
Serial.print("+");
Serial.print("+"); // Enter the AT mode
delay(500); // Slow down and wait for connectin establishment
}
void loop(){
Serial.println("AT+RSSI=?"); // Ask about the RSSI
for(int x=0 ; Serial.available() > 0 ; x++ ){ // get the Enter AT mode words
//delay(20); // Slow down for accuracy
Data[x] = Serial.read(); // Read and store Data Byte by Byte
if (Data[x] == Value ) // Look for the elemnt of the array that have "-" that's the start of the RSSI value
{
INDEX=x;
}
}
//Serial.println("AT+EXIT");
RAW[0] = Data[INDEX]; // Copy the RSSI value to RAW Char array
RAW[1] = Data[INDEX+1];
RAW[2] = Data[INDEX+2];
RAW[3] = Data[INDEX+3];
int RSSI = atoi(RAW); //Convert the Array to an integer
//Serial.println(RSSI);
//delay(200); // Give the program time to process. Serial Comm sucks
double D = exp(((RSSI+60)/-10)); //Calculate the distance but this is VERY inaccurate
//Serial.println(D);
if (D>1.00) // If the device gets far, excute the following>>
{
digitalWrite(13, HIGH);
digitalWrite(8, HIGH);
delay(500);
digitalWrite(13, LOW);
digitalWrite(8, LOW);
delay(500);
}
}
I'm trying to code an Arduino avoidance robot as a learning project. When I run the following code only one motor (the left one) works. If I comment out the if statement that uses the checkDistance() function and just loop the forward() function both motors work fine. I'm using an Adafruit Motorshield v1.2, and I believe this is the motor: Link. I've tried powering directly through USB, and also through external power supply (4 x AAs), and have the same issue. Any pointers would be appreciated. Thank you!
#include <AFMotor.h>
#define trigPin 3
#define echoPin 2
AF_DCMotor left_motor(2, MOTOR12_64KHZ); // create motor #1, 64KHz pwm
AF_DCMotor right_motor(1, MOTOR12_64KHZ); // motor #2\
int maxDistance = 30;
//int minDistance = 0;
void setup() {
Serial.begin(9600); // set up Serial library at 9600 bps
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
left_motor.setSpeed(255);
right_motor.setSpeed(255);
}
void forward(int delayTime) {
left_motor.run(FORWARD);
right_motor.run(FORWARD);
delay(delayTime);
}
void backward(int delayTime) {
left_motor.run(BACKWARD);
right_motor.run(BACKWARD);
delay(delayTime);
}
void stop(int delayTime) {
left_motor.run(RELEASE);
right_motor.run(RELEASE);
delay(delayTime);
}
void right(int delayTime) {
left_motor.run(FORWARD);
right_motor.run(BACKWARD);
delay(delayTime);
}
void left(int delayTime) {
left_motor.run(BACKWARD);
right_motor.run(FORWARD);
delay(delayTime);
}
int checkDistance(){
long duration, distance;
/* The following trigPin/echoPin cycle is used to determine the
distance of the nearest object by bouncing soundwaves off of it. */
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
//Calculate the distance (in cm) based on the speed of sound.
distance = duration/59.1;
return distance;
}
void loop() {
int currentDistance = checkDistance();
Serial.print(currentDistance);
if (currentDistance >= maxDistance){
Serial.println(" cm. No immediate obstacles detected. Moving forward.");
forward(2000);
stop(1000);
}
else {
Serial.println(" cm. Obstacle detected. Changing direction.");
right(1500);
stop(1000);
}
}
If I were trying to debug this, I would first test each of the motor functions without any logic check from the sensor. (e.g. do both wheels turn and in the correct direction when left, right, backward, etc are called just from loop()). That will give confidence that it is not a wiring or other hardware problem. If they don't work then sorting that out give you a place to start.
If they do work, then it must be the values with the sensor, right? How did you determine the maxDistancevalue? If it is too high then this line:
if (currentDistance >= maxDistance){
may never evaluate to true. You have some log statements in there so you have some sense of the value of currentDistance. Does it seem to be reflecting accurate values when you place objects at varying distances from the sensor?
Anyway... some thoughts.