通过板卡的485接口模拟dmx512协议进行控制sm16512ps灯带，通过以下方式初始化串口的引脚：
void dmx512_uart1_init(void){ GPIO_InitTypeDef GPIO_InitStruct = {0}; __HAL_RCC_USART1_CLK_ENABLE(); __HAL_RCC_GPIOA_CLK_ENABLE(); /**USART2 GPIO Configuration PD5 ------> USART2_TX PD6 ------> USART2_RX */ GPIO_InitStruct.Pin = GPIO_PIN_9|GPIO_PIN_10; GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH; GPIO_InitStruct.Alternate = GPIO_AF7_USART1; HAL_GPIO_Init(GPIOA, &GPIO_InitStruct); // PA9 PA10 huart1.Instance = USART1; huart1.Init.BaudRate = 250000; huart1.Init.WordLength = UART_WORDLENGTH_8B; huart1.Init.StopBits = UART_STOPBITS_2; huart1.Init.Parity = UART_PARITY_NONE; huart1.Init.Mode = UART_MODE_TX_RX; huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE; huart1.Init.OverSampling = UART_OVERSAMPLING_16; //设置接收端使用16倍采样 if (HAL_UART_Init(&huart1) != HAL_OK) { Error_Handler(); }}void dmx512_io_init(void){ GPIO_InitTypeDef GPIO_InitStruct = {0}; __HAL_RCC_GPIOA_CLK_ENABLE(); HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9|GPIO_PIN_10, GPIO_PIN_SET); GPIO_InitStruct.Pin = GPIO_PIN_9|GPIO_PIN_10; GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW; HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);}
通过复用串口TX引脚来输出dmx512协议的高低电平：
void dmx512_pin_mode(uint8_t mode){ if(mode) //mode=1，当串口发送用，在dmx512发送中主要用于发送数据帧 { dmx512_uart1_init(); } else if(mode == 0)//mode=0，当普通io用，在dmx512发送中主要用来形成break和mab信号 { dmx512_io_init(); }}int dmx512_uart1_send(uint8_t *buf,uint16_t size,uint32_t timeout){ uint8_t value; value = HAL_UART_Transmit(&huart1, buf, size, timeout); return value;}void dmx512_task(void *para){ uint8_t tx_data[4] = {0}; uint8_t start_code= 0; dmx512_pin_mode(0); HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_RESET); rt_us_delay(100); HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_SET); rt_us_delay(10); dmx512_pin_mode(1); dmx512_uart1_send(&start_code, sizeof(start_code), 0xFFFF); rt_thread_mdelay(1000); while(1) { tx_data[0] = 1; tx_data[1] = 0; tx_data[2] = 0; tx_data[3] = 0; dmx512_uart1_send(tx_data, sizeof(tx_data), 0xFFFF); rt_thread_mdelay(1000); }}
因为灯带是RGBW灯带，所以我以为是四个通道控制红、绿、蓝、白四种颜色，但是程序控制的灯带并没有亮起红色灯光，而是几个光的颜色切换一下后就再也不亮了。
有大佬能指点指点吗？
没有逻辑分析仪这种高端设备
调DMX512用这种就够了 https://item.taobao.com/item.htm?id=671664119953
@aozima
okok 感谢回复