问答

如下程序，使用DMA发送数据到USART2，单发USART正常发送，但用DMA批量发送不能启动：dmamux_event_generation_disable(DMAMUX_MUXCH2);//DMAMUX_MUXCH1dma_interrupt_disable(DMA0,DMA_CH3,DMA_INT_FTF);usart_transmit_config(USART2,USART_TRANSMIT_ENABLE);usart_flag_clear(USART2,USART_FLAG_TC);usart_dma_transmit_config(USART2,USART_DENT_ENABLE);//usart_dma_transmit_config(USART2,USART_DENT_DISABLE);dma_channel_disable(DMA0,DMA_CH3);//DMA_CH1->DMA_CH3//usart_data_transmit(USART2,0x55);dma_memory_address_config(DMA0,DMA_CH3,(uint32_t)lcdptr->lcdtx);dma_transfer_number_config(DMA0,DMA_CH3,lcdptr->lcdtxleng);dma_interrupt_flag_clear(DMA0,DMA_CH3,DMA_INT_FLAG_FTF);dma_interrupt_enable(DMA0,DMA_CH3,DMA_INT_FTF);dmamux_request_id_config(DMAMUX_MUXCH2,DMA_REQUEST_USART2_TX);dmamux_synchronization_disable(DMAMUX_MUXCH2);dma_channel_enable(DMA0,DMA_CH3);//dmamux_event_generation_enable(DMAMUX_MUXCH1);lcdptr->lcdst=TRANS_IN;有劳高手指点！！！！

如下程序，使用DMA发送数据到USART2，单发USART正常发送，但用DMA批量发送不能启动：dmamux_event_generation_disable(DMAMUX_MUXCH2);//DMAMUX_MUXCH1dma_interrupt_disable(DMA0,DMA_CH3,DMA_INT_FTF);usart_transmit_config(USART2,USART_TRANSMIT_ENABLE);usart_flag_clear(USART2,USART_FLAG_TC);usart_dma_transmit_config(USART2,USART_DENT_ENABLE);//usart_dma_transmit_config(USART2,USART_DENT_DISABLE);dma_channel_disable(DMA0,DMA_CH3);//DMA_CH1->DMA_CH3//usart_data_transmit(USART2,0x55);dma_memory_address_config(DMA0,DMA_CH3,(uint32_t)lcdptr->lcdtx);dma_transfer_number_config(DMA0,DMA_CH3,lcdptr->lcdtxleng);dma_interrupt_flag_clear(DMA0,DMA_CH3,DMA_INT_FLAG_FTF);dma_interrupt_enable(DMA0,DMA_CH3,DMA_INT_FTF);dmamux_request_id_config(DMAMUX_MUXCH2,DMA_REQUEST_USART2_TX);dmamux_synchronization_disable(DMAMUX_MUXCH2);dma_channel_enable(DMA0,DMA_CH3);//dmamux_event_generation_enable(DMAMUX_MUXCH1);lcdptr->lcdst=TRANS_IN;有劳高手指点！！！！