Hi,
I have more than 256 bytes to transmit out via uart. I check the example code in SDL, which triggers the pdma with sw, the fifo is 128 byte in deep, then it can only send 129 bytes after sw triggering. So i want to trig the pdma move one byte to fifo every time the scb send one byte out. Below is my code:
cy_en_scb_uart_status_t retStatus = CY_SCB_UART_BAD_PARAM;
uint32_t scb_index = ((uint32_t)base - SCB0_BASE) / 0x10000ul;
if(scb_index < SCB_NUM_MAX)
{
cy_stc_pdma_descr_config_t dw1ChUartTxConfig =
{
.deact = 0ul,
.intrType = CY_PDMA_INTR_DESCR_CMPLT,
.trigoutType = CY_PDMA_TRIGOUT_1ELEMENT_CMPLT,
.chStateAtCmplt = CY_PDMA_CH_DISABLED,
.triginType = CY_PDMA_TRIGIN_1ELEMENT,
.dataSize = CY_PDMA_BYTE,
.srcTxfrSize = 0ul, // same as "dataSize"
.destTxfrSize = 1ul, // 32bit width
.descrType = CY_PDMA_1D_TRANSFER,
.srcAddr = (void *)(src_buffer),
.destAddr = (void *)&base->unTX_FIFO_WR.u32Register,
.srcXincr = 1ul,
.destXincr = 0ul,
.xCount = tx_num,
.descrNext = NULL
};
cy_stc_pdma_chnl_config_t dwUartTxConfig =
{
.PDMA_Descriptor = &dwUartTxDescr[scb_index],
.preemptable = 0ul,
.priority = 0ul,
.enable = 1ul,
};
/* Initialize & Enable DMA */
Cy_PDMA_Disable(pstcPDMA);
Cy_PDMA_Chnl_DeInit(pstcPDMA, chNum);
Cy_PDMA_Descr_Init(&dwUartTxDescr[scb_index], &dw1ChUartTxConfig);
Cy_PDMA_Chnl_Init(pstcPDMA, chNum, &dwUartTxConfig);
Cy_PDMA_Chnl_Enable(pstcPDMA, chNum);
Cy_PDMA_Chnl_SetInterruptMask(pstcPDMA, chNum);
Cy_PDMA_Enable(pstcPDMA);
Cy_TrigMux_Connect1To1(trigLine, 0ul, TRIGGER_TYPE_LEVEL, 0ul);
Cy_SCB_UART_PutArray(base, &src_buffer[0], 1ul);
/* SW Trigger */
//Cy_TrigMux_SwTrigger(trigLine, TRIGGER_TYPE_EDGE, 1ul);
retStatus = CY_SCB_UART_SUCCESS;
}
The "trigLine" above is TRIG_OUT_1TO1_2_SCB_TX_TO_PDMA10.
My setup:
cyt4bf8, scb0_tx, pdma 1;
My code can only send out the first byte of buffer, so i thought the pdma input trigger failed.
How to modify it?
Regards.
