Posted on August 04, 2011 at 00:30Hi,
i used to program my stm32 discovery board via usb cable using SWD.
I used some example code and i think i disabled SWD debugging accidently.
Now i cant enable it back, the Keil software i use says that no target is connected and flash download failed. Can anyone help me to enable SWD back ? Is there any ways to reset stm32. Here's the example code i used :
main.c
&sharpinclude ''stm32f10x_lib.h''
/* function prototypes */
void RCC_Configuration(void);
void GPIO_Configuration(void);
void Delay(vu32 nCount);
/* entry point */
int main(void)
{
/* configure clock sources */
RCC_Configuration();
/* configure I/O ports */
GPIO_Configuration();
/* blinking loop */
while (1) {
/* change the PC7 state */
GPIO_WriteBit(GPIOC, GPIO_Pin_8, (BitAction)(1 - GPIO_ReadOutputDataBit(GPIOC, GPIO_Pin_8)));
/* wait */
Delay(0x5FFFF);
Delay(0x5FFFF);
Delay(0x5FFFF);
Delay(0x5FFFF);
Delay(0x5FFFF);
Delay(0x5FFFF);
}
}
/* set up clock sources */
void RCC_Configuration(void)
{
/* reset */
RCC_DeInit();
/* activate HSI (Internal High Speed oscillator) */
RCC_HSICmd(ENABLE);
while (RCC_GetFlagStatus(RCC_FLAG_HSIRDY) == RESET);
/* configure prescalers */
RCC_HCLKConfig(RCC_SYSCLK_Div1);// HCLK = 64 MHz, AHB
RCC_PCLK1Config(RCC_HCLK_Div2); // APB1 = 32 MHz
RCC_PCLK2Config(RCC_HCLK_Div1); // APB2 = 64 MHz
/* set up FLASH */
FLASH_SetLatency(FLASH_Latency_2);
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
/* set up PLL */
RCC_PLLConfig(RCC_PLLSource_HSI_Div2, RCC_PLLMul_16); // 64 MHz
RCC_PLLCmd(ENABLE);
while (RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET);
/* set up SYSCLK */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK); //SYSCLK = PLLCLK => 64 MHz
while (RCC_GetSYSCLKSource() != 0x08);
/* set up peripheral clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC | RCC_APB2Periph_AFIO, ENABLE);
}
/* configure I/O ports */
void GPIO_Configuration(void)
{
/* pin configuration parameters */
GPIO_InitTypeDef GPIO_InitStructure;
/* disable SWJ debug port - comment if you are using JTAG */
GPIO_PinRemapConfig(GPIO_Remap_SWJ_Disable, ENABLE);
/* configure PC7 as output push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_Init(GPIOC, &GPIO_InitStructure);
}
/* wait */
void Delay(vu32 nCount)
{
while (nCount--);
}
#swd-disable #bootloader-rom
