/* DMA routine for DAC example */
static void App_DMA_Test(void)
{
uint32_t tmp = 0;
volatile uint32_t i = 0;
/* Initialize GPDMA controller */
Chip_GPDMA_Init(LPC_GPDMA);
/* Setting GPDMA interrupt */
NVIC_DisableIRQ(DMA_IRQn);
NVIC_SetPriority(DMA_IRQn, ((0x01 << 3) | 0x01));
NVIC_EnableIRQ(DMA_IRQn);
/* Get the free channel for DMA transfer */
dmaChannelNum = Chip_DMA_GetFreeChannel(LPC_GPDMA, GPDMA_CONN_DAC);
/* Output DAC value until get 'x' character */
while (DEBUGIN() != 'x') {
/* Start D/A conversion */
tmp++;
if (tmp == (DATA_SIZE - 1)) {
tmp = 0;
}
/* pre-format the data to DACR register */
DMAbuffer = (uint32_t) (DAC_VALUE(tmp) | DAC_BIAS_EN);
for (i = 0; i < 0x10000; i++) ;
channelTC = 0;
Chip_DMA_Transfer(LPC_GPDMA, dmaChannelNum,
(uint32_t) &DMAbuffer,
GPDMA_CONN_DAC,
GPDMA_TRANSFERTYPE_M2P_CONTROLLER_DMA,
1);
/* Waiting for writing DAC value completed */
while (channelTC == 0) {}
}
/* Disable interrupts, release DMA channel */
Chip_DMA_Stop(LPC_GPDMA, dmaChannelNum);
NVIC_DisableIRQ(DMA_IRQn);
}
/* DeInitialize DMA for UART, free transfer channels and disable DMA interrupt */
static void App_DMA_DeInit(void)
{
Chip_DMA_Stop(LPC_GPDMA, dmaChannelNumTx);
Chip_DMA_Stop(LPC_GPDMA, dmaChannelNumRx);
NVIC_DisableIRQ(DMA_IRQn);
}
