DMA1 Does not Work With USART1 in stm32f103c8?

Question

I'm Trying to enable DMA1 with USART1 in stm32f103c8 but it does not work . i enabled the usart to work as transmitter . and then enabled the DMA1 and make this configuration to it 1-enable the DMA1 clock from RCC. 2-disabled the DMA1 Channel . 3-set the DMA1 channel periority as very high periority. 4-make the direction of DMA1 channel from memory to peripheral. 5-make the memory size and peripheral size as byte. 6-enable memory increment and disable peripheral increment. 7-disable circular mode. 8-set the DMA interrupt for transfer complete. 7-set the memory address buffer and set the peripheral address as usart1 data register. 8-set the number of times to dma transfer as 6 . 9-enable the DMA1 channel interrupt in the NVIC. 10-enable the DMAT in the usart1 to make the usart work with the DMA1 11-enable the DMA1 to Start work.

after all this configuration the DMA does not work but the usart work successfully . in the main code i make intialize the usart1 and then intialize the DMA1 as me said up and then empty while(1) . the terminal did not receive the string in the memory and the DMA did not go to the handler that mean the DMA does not work never why ?

u8 Buffer[6] = "hesham";
int main(void){
    /*--------------------------------------------------------------------------------------------*/
    RCC_VidInit();
    RCC_VidEnablePeripheralClock( APB2_BUS , IOPA_EN   );    //Enable PORTA  Clock
    RCC_VidEnablePeripheralClock( APB2_BUS , USART1_EN );    //Enable USART1 Clock
    RCC_VidEnablePeripheralClock( AHB_BUS  , DMA1_EN   );    //Enable DMA1   Clock
    /*--------------------------------------------------------------------------------------------*/
    NVIC_VidEnableIRQ( 14 );                                 //Enable The DMA1Channel4 Interrupt Inside The NVIC
    /*-------------------------------GPIO Configuration Of Tx And Rx------------------------------*/
    CLR_BIT( GPIOA->CRH , 4 ); SET_BIT( GPIOA->CRH , 5 );    //PIN9 (TX) Output With 2MHZ Speed
    CLR_BIT( GPIOA->CRH , 6 ); SET_BIT( GPIOA->CRH , 7 );    //Make Pin9 Alternative Func PushPull

    CLR_BIT( GPIOA->CRH , 8  ); CLR_BIT( GPIOA->CRH , 9  );  //Pin10 (RX) Input
    SET_BIT( GPIOA->CRH , 10 ); CLR_BIT( GPIOA->CRH , 11 );  //Make Pin10 Floating Input
    /*-----------------------------------------------USART1 Configuration--------- ---------------*/
    //Using The Deafult M Size = 8 bit And 1 Stop bit
    USART1->BRR = 0x341 ;                                     //Set The BaudRate = 9600 Of External Oscillator = 8MHZ
    SET_BIT( USART1->CR3 , 7 );                               //Enable Usart To Work With DMA As Transmitter (DMAT bit)
    SET_BIT( USART1->CR1 , 3 ); SET_BIT( USART1->CR1 , 13 );  //Enable The Transmitter (TE Bit) and Enable The USART (UE bit)
    /*-----------------------------------------------DMA1 Channel 4 Configuration-----------------*/
    CLR_BIT( DMA1_CHANNEL4->CCR , 0 );                        //Disable The DMA To Access The Registers
    SET_BIT( DMA1_CHANNEL4->CCR , 1 );                        //Enable The Trnasmit Complete Interrupt (TCIE)
    SET_BIT( DMA1_CHANNEL4->CCR , 4 );                        //DMA Direction Is From Memory To Peripheral
    CLR_BIT( DMA1_CHANNEL4->CCR , 5 );                        //Disable Circular
    CLR_BIT( DMA1_CHANNEL4->CCR , 6 );                        //Disable Peripheral Increment
    SET_BIT( DMA1_CHANNEL4->CCR , 7 );                        //Enable Memory Increment
    CLR_BIT( DMA1_CHANNEL4->CCR , 8  ); CLR_BIT( DMA1_CHANNEL4->CCR , 9  );  //Peripheral Size = BYTE
    CLR_BIT( DMA1_CHANNEL4->CCR , 10 ); CLR_BIT( DMA1_CHANNEL4->CCR , 11 );  //Memory Size = BYTE
    SET_BIT( DMA1_CHANNEL4->CCR , 12 ); SET_BIT( DMA1_CHANNEL4->CCR , 13 );  //Channel Priority = Very High
    CLR_BIT( DMA1_CHANNEL4->CCR , 14 );                                      //Disable Memory To Memory Mode
    DMA1_CHANNEL4->CPAR = (u32)USART1->DR ;                   //The Address Of Peripheral is Usart Data Reg
    DMA1_CHANNEL4->CMAR = Buffer ;                            //The Address Of Memory is Buffer
    DMA1_CHANNEL4->CNDTR = 6 ;                                //The Number Of Transfer Item Is = The Size Of Buffer = 6
    //Clear The DMA1 Flags Of Channel 4
    SET_BIT( DMA1->IFCR , 12 );SET_BIT( DMA1->IFCR , 13 );SET_BIT( DMA1->IFCR , 14 );SET_BIT( DMA1->IFCR , 15 );
    SET_BIT( DMA1_CHANNEL4->CCR , 0 );                        //Enable The DMA To Work
    /*--------------------------------------------------------------------------------------------*/
    while(1);

    return 0;
}

and this is the handler of the DMA

void DMA1_Channel4_IRQHandler(void){

    if( (GET_BIT( DMA1->ISR , 13 )) == 1 ){ //Checking About Transfer Complete Flag Of DMA
        //Clear The DMA1 Flags Of Channel 4
        SET_BIT( DMA1->IFCR , 12 );SET_BIT( DMA1->IFCR , 13 );SET_BIT( DMA1->IFCR , 14 );SET_BIT( DMA1->IFCR , 15 );
    }
}

can someone help me please ?

P__J__ my code is done by me i mean that i have been accessed the registers and make my drivers and someone tell me before that here no one can see my code if i have been did it by my self they need me to use the HALL function — Hesham Adel, Dec 02 '19 at 23:32
P__J__ can i upload my own code here ? to see it or you need a hall code ? — Hesham Adel, Dec 03 '19 at 04:25
If `no one can see my code` then `no one can answer your question` — 0___________, Dec 03 '19 at 09:26
Your if( (GET_BIT( DMA1->ISR , 13 )) == 1 ) should be if( (GET_BIT( DMA1->ISR , 13 )) != 0 ). Also, you should use the DEFINE instead of value hardcoded. I work with STM32F0 and F103. In my case, the DMA CCR does not have any flag 13 What do you mean with SET_BIT( DMA1_CHANNEL4->CCR , 4 ); Is it SET_BIT( DMA1_CHANNEL4->CCR , DMA_CCR_DIR ); — YvonBlais, Dec 04 '19 at 04:19
In the ISR register of the DMA the bit number 13 is the TCIF flag — Hesham Adel, Dec 04 '19 at 04:29
yes the SET_BIT( DMA1_CHANNEL4->CCR , 4 ); Is the SET_BIT( DMA1_CHANNEL4->CCR , DMA_CCR_DIR ); — Hesham Adel, Dec 04 '19 at 04:30
my if mean if the TCIF has been set go inside the if but it does not matter because the handler of the DMA does not come — Hesham Adel, Dec 04 '19 at 04:31
Are you sure that the Interrupts are active NVIC_SetPriority_(DMAn_Channely_IRQn, 0); NVIC_EnableIRQ(DMAn_Channely_IRQn); — YvonBlais, Dec 05 '19 at 00:42

score 0 · Answer 1 · answered Dec 08 '19 at 08:38

0

i have been solved my problem it was an error in the configuration . the error was when i'm passing the address of the data register i'm not passing the address already but i'm passing the value of the data register address

answered Dec 08 '19 at 08:38

Hesham Adel

1
3

DMA1 Does not Work With USART1 in stm32f103c8?

1 Answers1