fcapri
Hoe gaat het met u druk op het werk ?
mag ik nog 'n verzoek om hulp aan u doen ?
Ik wil graag de snelheid van mijn truck meten op 'n rollerbaan
daarvoor vond ik deze sketch;
//arduino bike speedometer w serial.print()
//by Amanda Ghassaei 2012
//https://www.instructables.com/id/Arduino-Bike-Speedometer/
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
*/
//calculations
//tire radius ~ 13.5 inches
//circumference = pi*2*r =~85 inches
//max speed of 35mph =~ 616inches/second
//max rps =~7.25
#define reed A0//pin connected to read switch
//storage variables
int reedVal;
long timer;// time between one full rotation (in ms)
float mph;
float radius = 13.5;// tire radius (in inches)
float circumference;
int maxReedCounter = 100;//min time (in ms) of one rotation (for debouncing)
int reedCounter;
void setup(){
reedCounter = maxReedCounter;
circumference = 2*3.14*radius;
pinMode(reed, INPUT);
// TIMER SETUP- the timer interrupt allows precise timed measurements of the reed switch
//for more info about configuration of arduino timers see http://arduino.cc/playground/Code/Timer1
cli();//stop interrupts
//set timer1 interrupt at 1kHz
TCCR1A = 0;// set entire TCCR1A register to 0
TCCR1B = 0;// same for TCCR1B
TCNT1 = 0;
// set timer count for 1khz increments
OCR1A = 1999;// = (1/1000) / ((1/(16*10^6))*8) - 1
// turn on CTC mode
TCCR1B |= (1 << WGM12);
// Set CS11 bit for 8 prescaler
TCCR1B |= (1 << CS11);
// enable timer compare interrupt
TIMSK1 |= (1 << OCIE1A);
sei();//allow interrupts
//END TIMER SETUP
Serial.begin(9600);
}
ISR(TIMER1_COMPA_vect) {//Interrupt at freq of 1kHz to measure reed switch
reedVal = digitalRead(reed);//get val of A0
if (reedVal){//if reed switch is closed
if (reedCounter == 0){//min time between pulses has passed
mph = (56.8*float(circumference))/float(timer);//calculate miles per hour
timer = 0;//reset timer
reedCounter = maxReedCounter;//reset reedCounter
}
else{
if (reedCounter > 0){//don't let reedCounter go negative
reedCounter -= 1;//decrement reedCounter
}
}
}
else{//if reed switch is open
if (reedCounter > 0){//don't let reedCounter go negative
reedCounter -= 1;//decrement reedCounter
}
}
if (timer > 2000){
mph = 0;//if no new pulses from reed switch- tire is still, set mph to 0
}
else{
timer += 1;//increment timer
}
}
void displayMPH(){
Serial.println(mph);
}
void loop(){
//print mph once a second
displayMPH();
delay(1000);
}
Heb 'n magneetje in 'n band ( omtrek band 23mm )geplakt en als opnemer 'n reedcontact no
voor 'n aTtiny85 of ( indien te weinig geheugen ) 'n arduino nano
met 0.91" 128x32 oled lcd display driver ic SSD1306
sketch zo compact mogelijk voor de aTtiny85
a.j nieuwlaat
Bij voorbaat bedankt
