[ARM] Reading input button on PC0 GPIO at STM32 ?

[bianchi77]

Guys,

How can I read a button from GPIO PC0 ?
I have created :

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Code C - [expand]
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RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOE | RCC_APB2Periph_GPIOA, ENABLE);
//initialize PC0 and PC1 as button input    
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 ;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; // this sets up input to be used with external push up/pull down resistors.
  GPIO_Init(GPIOC, &GPIO_InitStructure);
..
..
..
uint8_t button1;
     button1 = GPIO_ReadInputDataBit(GPIOC, GPIO_Pin_0);
 
         if (button1 == 0x00)
          {
             lcd_string("Button 1 is pressed..");
          }

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any opinions ?
thanks

 

[HsiueMingLee]

hi , u config the PC0 in "input pull down mode",so when you dont press the button , the level is always IO low (0), but if u press t button(if the button cennected GND) , the IO level is also low. i think you should make the 4th row " GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; " replce " GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; ". GPIO_Mode_IPD >>>> GPIO_Mode_IPD !!!

 

[bianchi77]

how can I wait for input from button0 ? PC0 ? so if user hasn't pressed the button, software will stop and wait... ?

 

[HsiueMingLee]

please upload ur whole codes here . u can write a "while loop or a for loop" to wait for input from button0, and External interrupt as well .

 

[bianchi77]

where will I put the "while" loop ? thanks

		 button1 = GPIO_ReadInputDataBit(GPIOC, GPIO_Pin_0);
	
			 if (button1 == RESET)
		//if (GPIO_ReadInputDataBit(GPIOC, GPIO_Pin_0) == 0x00) 
			  {
			     lcd_cmd(LCD_CLEAR);
				 lcd_string("Button 1 is pressed..");
			     vTaskDelay(2000);
			  }

 

[HsiueMingLee]

loop this part " if (button1 == RESET)
//if (GPIO_ReadInputDataBit(GPIOC, GPIO_Pin_0) == 0x00)
{
lcd_cmd(LCD_CLEAR);
lcd_string("Button 1 is pressed..");
vTaskDelay(2000);
}"

 

[bianchi77]

like this :

while (button1 != RESET )
{
if (button1 == RESET)
{
lcd_cmd(LCD_CLEAR);
lcd_string("Button 1 is pressed..");
vTaskDelay(2000);
}
}

?
Thanks

 

[HsiueMingLee]

no , add my qq account , add i give u a voice call there , and tell you how to modify the code ...its not convinient to type . and my qq account is :790912166.