I am hoping someone might know where I am going wrong, so I am completely new to both Arduino's and ESP32, mostly dabbled with Pi's, however, trying to do a project at mo to get ultrasonic sensors to respond quicker, so found a really useful site https://homediyelectronics.com/projects ... rupts/?p=4 covering how to use interrupts to get things to work a bit quicker.
I have tried to modify the sketch to better understand how it works, it does compile but when it goes onto the ESP32 it just keeps rebooting, was hoping someone could point me in the direction of the errors in my way!
Code: Select all
#define trigPin 23 // Pin 23 trigger output
#define echoPin 22 // Pin 22 Echo input
#define echo_int 0 // Interrupt id for echo pulse
#define TIMER_US 80 // 80 uS timer duration
#define TICK_COUNTS 4000 // 200 mS worth of timer ticks
volatile long echo_start = 0; // Records start of echo pulse
volatile long echo_end = 0; // Records end of echo pulse
volatile long echo_duration = 0; // Duration - difference between end and start
volatile int trigger_time_count = 0; // Count down counter to trigger pulse time
volatile long range_flasher_counter = 0; // Count down counter for flashing distance LED
hw_timer_t * Timer1 = NULL;
portMUX_TYPE timerMux = portMUX_INITIALIZER_UNLOCKED;
// --------------------------
// timerIsr() 50uS second interrupt ISR()
// Called every time the hardware timer 1 times out.
// --------------------------
void IRAM_ATTR timerIsr() {
portENTER_CRITICAL_ISR(&timerMux);
trigger_pulse();
portEXIT_CRITICAL_ISR(&timerMux);
}
// ----------------------------------
// setup() routine called first.
// A one time routine executed at power up or reset time.
// Used to initialise hardware.
// ----------------------------------
void setup()
{
pinMode(trigPin, OUTPUT); // Trigger pin set to output
pinMode(echoPin, INPUT); // Echo pin set to input
Timer1 = timerBegin(0, TIMER_US, true); // Initialise timer 1
timerAttachInterrupt(Timer1, &timerIsr, true); // Attach interrupt to the timer service routine
timerAttachInterrupt(echo_int, echo_interrupt, CHANGE); // Attach interrupt to the sensor echo input
Serial.begin (9600); // Initialise the serial monitor output
}
// ----------------------------------
// loop() Runs continuously in a loop.
// This is the background routine where most of the processing usualy takes place.
// Non time critical tasks should be run from here.
// ----------------------------------
void loop()
{
Serial.println(echo_duration / 58); // Print the distance in centimeters
delay(100); // every 100 mS
}
// --------------------------
// trigger_pulse() called every 10 uS to schedule trigger pulses.
// Generates a pulse one timer tick long.
// Minimum trigger pulse width for the HC-SR04 is 10 us. This system
// delivers a 10 uS pulse.
// --------------------------
void trigger_pulse()
{
static volatile int state = 0; // State machine variable
if (!(--trigger_time_count)) // Count to 200mS
{ // Time out - Initiate trigger pulse
trigger_time_count = TICK_COUNTS; // Reload
state = 1; // Changing to state 1 initiates a pulse
}
switch(state) // State machine handles delivery of trigger pulse
{
case 0: // Normal state does nothing
break;
case 1: // Initiate pulse
digitalWrite(trigPin, HIGH); // Set the trigger output high
state = 2; // and set state to 2
break;
case 2: // Complete the pulse
default:
digitalWrite(trigPin, LOW); // Set the trigger output low
state = 0; // and return state to normal 0
break;
}
}
// --------------------------
// echo_interrupt() External interrupt from HC-SR04 echo signal.
// Called every time the echo signal changes state.
//
// Note: this routine does not handle the case where the timer
// counter overflows which will result in the occassional error.
// --------------------------
void echo_interrupt()
{
switch (digitalRead(echoPin)) // Test to see if the signal is high or low
{
case HIGH: // High so must be the start of the echo pulse
echo_end = 0; // Clear the end time
echo_start = micros(); // Save the start time
break;
case LOW: // Low so must be the end of hte echo pulse
echo_end = micros(); // Save the end time
echo_duration = echo_end - echo_start; // Calculate the pulse duration
break;
}
}
// --------------------------
// distance_flasher() Called from the timer 1 timerIsr service routine.
// Flashes the onboard LED at a rate inversely proportional
// to distance. The closer it gets the higher the frequency.
// --------------------------
void distance_flasher()
{
if (--range_flasher_counter <= 0) // Decrement and test the flash timer
{ // Flash timer time out
if (echo_duration < 25000) // If the echo duration is within limits
{
range_flasher_counter = echo_duration * 2; // Reload the timer with the current echo duration
}
else
{
range_flasher_counter = 25000; // If out of range use a default
}
}
}Code: Select all
ets Jun 8 2016 00:22:57
rst:0xc (SW_CPU_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fff0030,len:1324
ho 0 tail 12 room 4
load:0x40078000,len:13480
ho 0 tail 12 room 4
load:0x40080400,len:3604
entry 0x400805f0
Guru Meditation Error: Core 1 panic'ed (LoadProhibited). Exception was unhandled.
Core 1 register dump:
PC : 0x400d15ef PS : 0x00060d30 A0 : 0x800d1064 A1 : 0x3ffb27d0
A2 : 0x00000000 A3 : 0x400d0fdc A4 : 0x00000001 A5 : 0x3ffbdb70
A6 : 0x00000000 A7 : 0x003fffff A8 : 0x800d162c A9 : 0x3ffb27a0
A10 : 0x00000000 A11 : 0x00000000 A12 : 0x40081100 A13 : 0x3ffb8a88
A14 : 0x00000000 A15 : 0x3ffc1228 SAR : 0x00000020 EXCCAUSE: 0x0000001c
EXCVADDR: 0x00000001 LBEG : 0x40085c18 LEND : 0x40085c23 LCOUNT : 0xffffffff
Backtrace:0x400d15ec:0x3ffb27d00x400d1061:0x3ffb27f0 0x400d1d26:0x3ffb2820
ELF file SHA256: 0000000000000000