Posted on February 19, 2014 at 13:50
T0H = 0.35 us, T1H = 0.70 us and TH+TL = 1.25 us. I set up timer4 to generate square wave on channel 2 and i'im planning to use dma to copy to the TIM4->CCR2 the time value for te current bit from a prepoulated array. Here is my current code GPIO_InitTypeDef GPIO_InitStructure; TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; TIM_OCInitTypeDef TIM_OCInitStructure; DMA_InitTypeDef DMA_InitStructure; //Enable TIM4,GPIOD,DMA2 Clock RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4,ENABLE); RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD,ENABLE); RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2,ENABLE); GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN; GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13; GPIO_PinAFConfig(GPIOD, GPIO_PinSource13, GPIO_AF_TIM4); GPIO_Init(GPIOD, &GPIO_InitStructure); TIM_OCStructInit(&TIM_OCInitStructure); TIM_TimeBaseStructure.TIM_Prescaler = 0; TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; TIM_TimeBaseStructure.TIM_Period = RGB_PULSE_PERIOD; TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure); /* PWM1 Mode configuration: Channel2 */ TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = 1; TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; TIM_OC2Init(TIM4, &TIM_OCInitStructure); /* DMA2 Channel 0 Config */ DMA_DeInit(DMA2_Stream0); DMA_InitStructure.DMA_Channel = DMA_Channel_0; DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&TIM4->CCR2;//(uint32_t)0x40000838; DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)Ch1Buffer; DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; DMA_InitStructure.DMA_BufferSize = RGB_BUFFER_SIZE; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord; DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; DMA_InitStructure.DMA_Priority = DMA_Priority_High; DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full; DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; DMA_Init(DMA2_Stream0,&DMA_InitStructure); TIM_DMACmd(TIM4, TIM_DMA_CC2, ENABLE); followed by the call of this function void RgbSendFrame(uint8_t Channel, uint8_t* Buffer, uint16_t Size) { uint8_t i,j,bit; bit = 0x80; j = 0; if(Channel & 0x01) { while(Size) { for (i = 0; i < 8; i++) { if(*Buffer & bit) { Ch1Buffer[j] = RGB_PULSE_1; }else { Ch1Buffer[j] = RGB_PULSE_0; } j++; bit >>= 1; } bit = 0x80; Buffer++; Size--; } while(j < RGB_BUFFER_SIZE) { Ch1Buffer[j] = 0; j++; } TIM4->CCR2 = 1; DMA_SetCurrDataCounter(DMA2_Stream0, RGB_BUFFER_SIZE); DMA_Cmd(DMA2_Stream0,ENABLE); TIM_Cmd(TIM4, ENABLE); LedOn(2); while(DMA_GetFlagStatus(DMA2_Stream0,DMA_FLAG_TCIF0) == RESET); LedOff(2); TIM_Cmd(TIM4, DISABLE); DMA_Cmd(DMA2_Stream0, DISABLE); DMA_ClearFlag(DMA2_Stream0,DMA_FLAG_TCIF0); }//Fine Canale1 } Nothing works, the code get stuck while waiting for the dma to complete transfer. Some help would be great #rtfm
Good morning, i have to drive WS2812 led wich require a square wave with this timing
T0H = 0.35 us, T1H = 0.70 us and TH+TL = 1.25 us. I set up timer4 to generate square wave on channel 2 and i'im planning to use dma to copy to the TIM4->CCR2 the time value for te current bit from a prepoulated array. Here is my current code GPIO_InitTypeDef GPIO_InitStructure; TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; TIM_OCInitTypeDef TIM_OCInitStructure; DMA_InitTypeDef DMA_InitStructure; //Enable TIM4,GPIOD,DMA2 Clock RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4,ENABLE); RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD,ENABLE); RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2,ENABLE); GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN; GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13; GPIO_PinAFConfig(GPIOD, GPIO_PinSource13, GPIO_AF_TIM4); GPIO_Init(GPIOD, &GPIO_InitStructure); TIM_OCStructInit(&TIM_OCInitStructure); TIM_TimeBaseStructure.TIM_Prescaler = 0; TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; TIM_TimeBaseStructure.TIM_Period = RGB_PULSE_PERIOD; TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure); /* PWM1 Mode configuration: Channel2 */ TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = 1; TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; TIM_OC2Init(TIM4, &TIM_OCInitStructure); /* DMA2 Channel 0 Config */ DMA_DeInit(DMA2_Stream0); DMA_InitStructure.DMA_Channel = DMA_Channel_0; DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&TIM4->CCR2;//(uint32_t)0x40000838; DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)Ch1Buffer; DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; DMA_InitStructure.DMA_BufferSize = RGB_BUFFER_SIZE; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord; DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; DMA_InitStructure.DMA_Priority = DMA_Priority_High; DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full; DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; DMA_Init(DMA2_Stream0,&DMA_InitStructure); TIM_DMACmd(TIM4, TIM_DMA_CC2, ENABLE); followed by the call of this function void RgbSendFrame(uint8_t Channel, uint8_t* Buffer, uint16_t Size) { uint8_t i,j,bit; bit = 0x80; j = 0; if(Channel & 0x01) { while(Size) { for (i = 0; i < 8; i++) { if(*Buffer & bit) { Ch1Buffer[j] = RGB_PULSE_1; }else { Ch1Buffer[j] = RGB_PULSE_0; } j++; bit >>= 1; } bit = 0x80; Buffer++; Size--; } while(j < RGB_BUFFER_SIZE) { Ch1Buffer[j] = 0; j++; } TIM4->CCR2 = 1; DMA_SetCurrDataCounter(DMA2_Stream0, RGB_BUFFER_SIZE); DMA_Cmd(DMA2_Stream0,ENABLE); TIM_Cmd(TIM4, ENABLE); LedOn(2); while(DMA_GetFlagStatus(DMA2_Stream0,DMA_FLAG_TCIF0) == RESET); LedOff(2); TIM_Cmd(TIM4, DISABLE); DMA_Cmd(DMA2_Stream0, DISABLE); DMA_ClearFlag(DMA2_Stream0,DMA_FLAG_TCIF0); }//Fine Canale1 } Nothing works, the code get stuck while waiting for the dma to complete transfer. Some help would be great #rtfm
