LeafLabs Garden » Topic: Using Interrupts

LeafLabs Garden » Topic: Using Interrupts http://forums.leaflabs.com/topic.php?id=9473 A place to share, learn, and grow... en-US Fri, 22 Jan 2016 00:21:40 +0000 http://bbpress.org/?v=1.0.2 <![CDATA[Search]]> q http://forums.leaflabs.com/search.php gbulmer on "Using Interrupts" http://forums.leaflabs.com/topic.php?id=9473#post-20945 Sat, 10 Nov 2012 05:51:25 +0000 gbulmer 20945@http://forums.leaflabs.com/ Bernardo769 - There error message is accurate and complete. There is no member of <code>class voieRC</code> called <code>ptr</code>, and if there were, it could not be a member, it must be a static member function, or pointer to a simple function. Maybe you should solve the problem using C first, rather than introduce an extra source of bugs and misunderstanding? Bernardo769 on "Using Interrupts" http://forums.leaflabs.com/topic.php?id=9473#post-20936 Sat, 10 Nov 2012 03:26:50 +0000 Bernardo769 20936@http://forums.leaflabs.com/ Thank you for your clarification. I noticed that determine which pin triggered an interrupt can be a bit complicated. My knowledge of register management are limited. I do not engage in this way for now. But if there is a tutorial to do some testing, I'm interested. I looked for a solution using C++ classes: <pre><code>#include "voieRC.h" #define Serial SerialUSB voieRC bouton(20); void setup() { attachInterrupt(20, bouton.*ptr, CHANGE); // Ne fonctionne pas : error: invalid use of non-static member function } void loop() { SerialUSB.println(bouton.valeur()); delay(500); } voieRC::voieRC(int pin){ pinRC = pin; pinMode(pin, INPUT_PULLUP); } unsigned int voieRC::valeur() const{ return (timeDOWN - timeUP); } void voieRC::etat() { if (digitalRead(this->pinRC) == HIGH) { // Front montant timeUP = micros(); timeDOWN = micros(); } else { // Front descendant timeDOWN = micros(); } }</code></pre> With voieRC.h = <pre><code>class voieRC{ public: voieRC(int); unsigned int valeur() const; void etat(); private: int pinRC; unsigned int timeUP; unsigned int timeDOWN; };</code></pre> I get a compilation error: <pre><code>attachInterrupt(20, bouton.*ptr, CHANGE); // error: invalid use of non-static member function</code></pre> I tried to "cast" the pointer recover: <pre><code>void (voieRC::*ptr)() = &voieRC::etat; //On déclare un pointeur sur la fonction membre voieRC bouton(20); void setup() { void (*ptrw)() = (void (*)()) bouton.*ptr; // Ne fonctionne pas : error: invalid cast from type 'voieRC' to type 'void (*)()' attachInterrupt(20, *ptrw, CHANGE); }</code></pre> But it does not. gbulmer on "Using Interrupts" http://forums.leaflabs.com/topic.php?id=9473#post-20926 Fri, 09 Nov 2012 18:22:22 +0000 gbulmer 20926@http://forums.leaflabs.com/ Bernardo769 - figuring out which pin triggered an interrupt can be a bit involved. The easiest way is to have a different interrupt handler for each pin: <pre><code>volatile int state_pin20 = LOW; volatile int state_pin21 = LOW; void setup() { pinMode(BOARD_LED_PIN, OUTPUT); pinMode(20, INPUT); attachInterrupt(20, blink, CHANGE); pinMode(21, INPUT); attachInterrupt(21, blink, CHANGE); } void loop() { digitalWrite(BOARD_LED_PIN, (state_pin20 || state_pin21)); } void blink20() { // pin had interrupt state_pin20 = !state_pin20; } void blink21() { // pin had an interrupt state_pin21 = !state_pin21; }</code></pre> Could you ue that approach? If not, you need to look in EXTI_PR register. The way interrupt pins are set up is a bit odd. There is not a unique pin interrupt id for every pin. I/O pins are grouped into 16-pin ports, and a Maple has several ports. To figure out which pin has triggered, you'll need to figure out which port, and pin within that port, a Maple pin number corresponds to. There is a table at <a href="http://leaflabs.com/docs/hardware/maple.html#gpio-port-pin-map" rel="nofollow">http://leaflabs.com/docs/hardware/maple.html#gpio-port-pin-map</a> which tells you. IIRC, all the pin 0's on all ports share 1 set of trigger control and flags. All the pin 1's on all ports share a 2nd set of trigger control and flags. and so on So once you know the pin number within the port, you can check that flag within EXTI_PR. This is all described in loving detail in the STM32F103 RM0008 manual, which you can download from ST Micro. Bernardo769 on "Using Interrupts" http://forums.leaflabs.com/topic.php?id=9473#post-20899 Fri, 09 Nov 2012 00:45:59 +0000 Bernardo769 20899@http://forums.leaflabs.com/ Sorry if I was not specific enough. I rephrase my question: <pre><code>volatile int state_pin20 = LOW; volatile int state_pin21 = LOW; void setup() { pinMode(BOARD_LED_PIN, OUTPUT); pinMode(20, INPUT); attachInterrupt(20, blink, CHANGE); pinMode(21, INPUT); attachInterrupt(21, blink, CHANGE); } void loop() { digitalWrite(BOARD_LED_PIN, (state_pin20 || state_pin21)); } void blink() { // test pin has an interrupt if (pin20) { // How to test here to see the pin20 triggered interrupt? ... state_pin20 = !state_pin20; } if (pin21) { how to test here? ... state_pin21 = !state_pin21; } }</code></pre> thank you for your help gbulmer on "Using Interrupts" http://forums.leaflabs.com/topic.php?id=9473#post-20894 Thu, 08 Nov 2012 19:42:56 +0000 gbulmer 20894@http://forums.leaflabs.com/ Bernardo769 - <blockquote>In the blink function, is it possible to know what has triggered the interrupt pin? </blockquote> I don't think I understand the question. Are you asking: A. "can the interrupt service routine (blink) work out which pin triggered the interrupt that called the (blink) function", or B. "what kind of signal triggered the pin, was it a rising edge, falling edge, ..." or C. something else? BTW <pre><code>void blink() { // test pin has an interrupt // ????? if (state == HIGH) { state = LOW; } else { // state must be LOW state = HIGH; } }</code></pre> can be rewritten as: <pre><code>void blink() { // test pin has an interrupt // ????? state = !state; }</code></pre> Bernardo769 on "Using Interrupts" http://forums.leaflabs.com/topic.php?id=9473#post-20874 Thu, 08 Nov 2012 04:39:01 +0000 Bernardo769 20874@http://forums.leaflabs.com/ Hi, in this example : <pre><code>volatile int state = LOW; void setup() { pinMode(BOARD_LED_PIN, OUTPUT); pinMode(20, INPUT); attachInterrupt(20, blink, CHANGE); pinMode(21, INPUT); attachInterrupt(21, blink, CHANGE); } void loop() { digitalWrite(BOARD_LED_PIN, state); } void blink() { // test pin has an interrupt // ????? if (state == HIGH) { state = LOW; } else { // state must be LOW state = HIGH; } }</code></pre> Blink function is attached to two interruptions for pins 20 and 21 : <pre><code>attachInterrupt(20, blink, CHANGE); attachInterrupt(21, blink, CHANGE);</code></pre> In the blink function, is it possible to know what has triggered the interrupt pin? Thank you for your answers