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LPC1769 SSP DMA data transfer

Question asked by Dhananjay J on Dec 30, 2016

I'm using the LPC1769 controller in my project, I'm transferring the data using SSP DMA to slave but the problem there I found missing clock pulses while transferring data. Captured signals using Logic analyzer is attached below and my code for initiating the transmission also given below, Please help me if anyone finds the issue. 



void DMA_IRQHandler(void) { if (Chip_GPDMA_Interrupt(LPC_GPDMA, DmaChExtFlashWrt) == SUCCESS) { isDmaTxfCompleted = 1; Chip_GPDMA_ChannelCmd(LPC_GPDMA, DmaChExtFlashWrt, DISABLE); Chip_SSP_DMA_Disable(LPC_SSP1); return; } } uint8_t SPI_WriteBufferDMA(uint8_t *pTxBuff, uint16_t Len) { isDmaTxfCompleted = 0; Chip_GPDMA_Transfer(LPC_GPDMA, DmaChExtFlashWrt, (uint32_t) pTxBuff, GPDMA_CONN_SSP1_Tx, GPDMA_TRANSFERTYPE_M2P_CONTROLLER_DMA, Len); Chip_SSP_DMA_Enable(LPC_SSP1); uint32_t tcnt = 50000000; while (isDmaTxfCompleted == 0) { tcnt--; if (tcnt == 0) break; } Chip_GPDMA_ChannelCmd(LPC_GPDMA, GPDMA_CONN_SSP1_Tx, DISABLE); Chip_SSP_DMA_Disable(LPC_SSP1); return 0; }

Original Attachment has been moved to: 24-MHz-2-B-Samples-[2]