STM32 actual combat button lights up LED (interrupt)

Let's take a look at the simplest experiment of lighting a lamp. The experiment requires you to use KEY4*4 buttons. Press the button to turn on the light, and lift the button to turn off the light, and repeat this cycle:

The idea of ​​the program is as follows:

1. The first thing you need to set is the clock: you turn on the clock of the port to which you connect the pin of the lamp. For example, if the lamp is connected to a pin of port A, you need to turn on the clock of port A.

2. Secondly, set the pins (we need to set the pins of the LED and a key in the matrix keyboard): We need to initialize the GPIO. We only need to call the GPIO_InitTypeDef structure and set each member. We need to set the position of the PIN pin GPIO_Pin, the speed of the pin GPIO_Speed, and the working state of the pin GPIO_Mode. Finally, call the initialization function GPIO_Init.

3. Then start writing our main function: If I want to set the pin of the LED lamp to a high level, I only need to call the GPIO_SetBits function, which sets the pin to a high level. If I want to set it to a low level, I just call the GPIO_ResetBits function.

4. Finally, we need to make it light up when pressed and go out when lifted, so we need an if statement

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Below is the program: The chip used is STM32F103C8T6, the LED control pin is C13, and the matrix keyboard is B9

The first step is to control the small light to be a push-pull output

void LED_Init (void)

{

GPIO_InitTypeDef GPIO_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC,ENABLE); //Initialize GPIOC clock

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;

GPIO_Init(GPIOC, &GPIO_InitStructure);

}

Then configure the matrix keyboard

void KEY_Init (void)

{

GPIO_InitTypeDef GPIO_InitStructure; //Configure PB9 pull-up input

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE); //Initialize GPIOB clock

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;

GPIO_Init(GPIOB, &GPIO_InitStructure);

}

Next is the main function

int main()

{

LED_Heat();

KEY_Init();

while(1)

{

LED = 1;

if(KEY == 0)

{

LED = 0;

}

}

}