Interrupt problem and UART problem

[randyao12345]

Posted on December 05, 2014 at 03:03

Hi ST forum,

I have two separate problems: 1. How do I configure an interrupt to do X on rising edge and Y on falling edge? Currently, I can only do rising edge: (Solved, see below)

/*********************************************************************************************************

 

** Function name:           EXTI_PA0_Config

 

** Descriptions:            Configures interrupt for PA0

 

** Parameters: None

 

*********************************************************************************************************/

 

 

 

void EXTI_PA0_Config(void)

 

{

 

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE);

 

RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);

 

 

 

GPIO_main.GPIO_Mode = GPIO_Mode_IN;

 

GPIO_main.GPIO_Speed = GPIO_Speed_25MHz;

 

GPIO_main.GPIO_PuPd = GPIO_PuPd_NOPULL;

 

GPIO_main.GPIO_Pin = GPIO_Pin_0; //Output PA0

 

GPIO_Init(GPIOA,&GPIO_main);

 

 

 

EXTI_main.EXTI_Line = EXTI_Line0;

 

EXTI_main.EXTI_Mode = EXTI_Mode_Interrupt;

 

EXTI_main.EXTI_Trigger = EXTI_Trigger_Rising; //need raising falling

 

EXTI_main.EXTI_LineCmd = ENABLE;

 

EXTI_Init(&EXTI_main);

 

 

 

SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource0);

 

 

 

NVIC_main.NVIC_IRQChannel = EXTI0_IRQn; //connect EXTI to line 0

 

NVIC_main.NVIC_IRQChannelPreemptionPriority = 0x01;  //set both preemptive priority and sub-priority to lowest

 

NVIC_main.NVIC_IRQChannelSubPriority = 0x01;

 

NVIC_main.NVIC_IRQChannelCmd = ENABLE;

 

NVIC_Init(&NVIC_main);

 

}

 

 

 

void EXTI0_IRQHandler(void){

 

    NVIC_ClearPendingIRQ(EXTI0_IRQn);

 

 

 

    if(flag==0)

 

    {

 

    flag=1;

 

    }

 

    else if(flag==1)

 

    {

 

    flag=0;

 

    }

 

    EXTI->PR|=(1<<0); //write 1 to PR to clear - write 1 at bit 0?

 

}

 

Problem 2: I want to be able to receive UART. Currently I can only transmit UART. (Partially solved with bugs, see below)

/*********************************************************************************************************

 

** Function name:           UART1_Init

 

** Descriptions:            Initializes UART2_TX at PA2

 

** Parameters: None

 

*********************************************************************************************************/

 

 

 

void UART1_Init(void)

 

{

 

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);

 

    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

 

 

 

    GPIO_main.GPIO_Pin = GPIO_Pin_2;

 

GPIO_main.GPIO_Mode = GPIO_Mode_AF;

 

GPIO_main.GPIO_PuPd = GPIO_PuPd_UP;

 

GPIO_main.GPIO_Speed = GPIO_Speed_50MHz;

 

GPIO_main.GPIO_OType = GPIO_OType_PP;

 

GPIO_Init(GPIOA, &GPIO_main);

 

 

 

GPIO_PinAFConfig(GPIOA,GPIO_PinSource2,GPIO_AF_USART2);

 

 

 

USART_main.USART_Mode = USART_Mode_Tx; //Transmit Mode, Receiver mode not currently required

 

USART_main.USART_BaudRate = 115200; //This is right

 

USART_main.USART_WordLength = USART_WordLength_8b; //8 bit data transmit

 

USART_main.USART_Parity = USART_Parity_No; //

 

USART_main.USART_StopBits = USART_StopBits_1; // 1 stop bit

 

USART_main.USART_HardwareFlowControl =     USART_HardwareFlowControl_None;

 

USART_Init(USART2,&USART_main);

 

        USART_Cmd(USART2,ENABLE);

 

}

[randyao12345]

Posted on December 12, 2014 at 19:10

I got the interrupt problem solved by doing this (after entering interrupt, check for port level).

void EXTI9_5_IRQHandler(void)

 

{

 

if (EXTI_GetITStatus(EXTI_Line5) != RESET) //Filter line 5

 

{

 

   EXTI_ClearITPendingBit(EXTI_Line5);

 

   if(GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_5))

 

   {

 

    GPIOD->BSRRL = GPIO_Pin_12; //test and debug only

 

    flag = 1;

 

   }

 

   else if(!GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_5))

 

   {

 

    GPIOD->BSRRH = GPIO_Pin_12; //test and debug only

 

    flag = 0;

 

   }

 

//    UART1_Send(Message_StopMotor,5);

 

}

 

}

 

For the UART, I'm stuck on this problem: I'm doing a loopback test, but valid data only displays 3500 baud or below. Over 4000 it displays some nonsense..

 

 

Here's my codes:

void UART1_Init(void)

{

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);

    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE);

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG,ENABLE);

    GPIO_main.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10;

GPIO_main.GPIO_Mode = GPIO_Mode_AF;

// GPIO_main.GPIO_PuPd = GPIO_PuPd_UP;

GPIO_main.GPIO_Speed = GPIO_Speed_50MHz;

// GPIO_main.GPIO_OType = GPIO_OType_PP;

GPIO_Init(GPIOA, &GPIO_main);

GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1);

GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1);

USART_main.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //Transmit Mode, Receiver mode not currently required

USART_main.USART_BaudRate = 3500; //Current baud rate 115200 bit/s

USART_main.USART_WordLength = USART_WordLength_8b; //8 bit data transmit

USART_main.USART_Parity = USART_Parity_No; //No parity bits

USART_main.USART_StopBits = USART_StopBits_1; // 1 stop bit

USART_main.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

// USART_Init(USART1,&USART_main);

//  USART_Cmd(USART1,ENABLE);

    USART_ITConfig(USART1, USART_IT_RXNE, ENABLE); //enables

USART_Init(USART1,&USART_main);

USART_Cmd(USART1, ENABLE);

    NVIC_main.NVIC_IRQChannel = USART1_IRQn;        // we want to configure the USART1 interrupts

    NVIC_main.NVIC_IRQChannelPreemptionPriority = 0;         // this sets the priority group of the USART1 interrupts

    NVIC_main.NVIC_IRQChannelSubPriority = 0; // this sets the subpriority inside the group

    NVIC_main.NVIC_IRQChannelCmd = ENABLE; // the USART1 interrupts are globally enabled

NVIC_Init(&NVIC_main);        // the properties are passed to the NVIC_Init function which takes care of the low level stuff

}

void USART1_IRQHandler(void)

{

if (USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)

{

// USART_ClearITPendingBit(USART1, USART_IT_RXNE);

// rx[rx_index] = USART_ReceiveData(USART1);

rx[rx_index] = USART1->DR;

if(rx_index>9)

{

rx_index = 0;

}

rx_index++;

}

}

in main:

int main(void)

{

LED_Init(); //Initializes LED outputs

UART1_Init(); //Initializes UART1 at PA9

EXTI_PB5_Config(); //Configures interrupt for PB5

int k = 0;

UART1_Send(Message_SetSpeed,7);

    while(1)

    {

    for(k=0;k<rx_index;k++)

    {

    printf(''\n%d: %X'',k,rx[k]);

    }

    }

}

(Set speed was defined as: uint8_t Message_SetSpeed[6] = {0x01,0xA1,0x9C,0x40,0x82,0x04}; //Speed set at 4000RPM)

[Tesla DeLorean]

Posted on December 12, 2014 at 21:21

What board are you doing this on? The STM32F4-DISCO has a huge bulk capacitor hung off the USART1 pins, which is going to limit it's rate/usability.

[randyao12345]

Posted on December 12, 2014 at 22:25

I am using the discovery board. Maybe that is the problem? Thus switching to USART2/3 would solve the problem?