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#include <mraa.h> |
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#include <inttypes.h> |
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#define LED_PIN 5 /**< The pin where the LED is connected */ |
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#define BTN_PIN 6 /**< Button is connected to this pin */ |
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int main(void) |
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{ |
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mraa_gpio_context ledPin; /* Will be used to represnt the LED pin */ |
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mraa_gpio_context btnPin; /* Will be used to represnt the button pin */ |
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uint32_t toggle; /* Used to toggle the LED */ |
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uint32_t btnState; /* Used to capture the state of the button */ |
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/* Step1: Init the mraa subsystem */ |
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mraa_init(); |
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/* Step2: Set the ledPin as port D5 and btnPin as port D6*/ |
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ledPin = mraa_gpio_init(LED_PIN); |
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btnPin = mraa_gpio_init(BTN_PIN); |
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/* Step3: Set the 'ledPin(D5)' pin as output */ |
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mraa_gpio_dir(ledPin, MRAA_GPIO_OUT); |
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/* LED is turned off to start with */ |
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toggle = 0; |
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mraa_gpio_write(ledPin, toggle); |
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/* |
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* Step4: Set the 'btnPin(D6)' pin as input, will be used to read |
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* the button state |
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*/ |
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mraa_gpio_dir(btnPin, MRAA_GPIO_IN); |
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while(1) |
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{ |
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/* Step5: Wait until there is some activty on the button pin */ |
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while (mraa_gpio_read(btnPin) != 0) |
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{ } |
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/* |
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* Step6: Button state has changed, wait for signal to settle, and |
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* then read the pin again to get the 'stable' signal, this is |
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* simplest form of debouncing. |
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*/ |
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usleep(10); /* man usleep */ |
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if (mraa_gpio_read(btnPin) == 1) |
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{ |
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/* Step7: Control the LED state based on the button toggle */ |
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if (toggle == 0) |
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{ |
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toggle = 1; /* If the LED is off, trun it on */ |
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} |
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else |
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{ |
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toggle = 0; /* Turn off the LED */ |
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} |
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mraa_gpio_write(ledPin, toggle); |
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} |
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// else: false click, ignore it |
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} |
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return 0; |
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} |
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