void Start_DMA_Playback() {
#if 0 // old demo code
if (DMA_Playback_Count == 0)
return;
#endif
DMAMUX0->CHCFG[0] = DMAMUX_CHCFG_SOURCE(54);
// initialize source and destination pointers
DMA0->DMA[0].SAR = DMA_SAR_SAR((uint32_t) Reload_DMA_Source);
DMA0->DMA[0].DAR = DMA_DAR_DAR((uint32_t) (&(DAC0->DAT[0])));
// byte count
DMA0->DMA[0].DSR_BCR = DMA_DSR_BCR_BCR(Reload_DMA_Byte_Count);
// verify done flag is cleared
DMA0->DMA[0].DSR_BCR &= ~DMA_DSR_BCR_DONE_MASK;
DMAMUX0->CHCFG[0] |= DMAMUX_CHCFG_ENBL_MASK;
// start the timer running
TPM0_Start();
}
//======================================================================
//函数名称：DMA_Init()
//函数功能：初始化1个DMA模块
//输 入：DMA_Struct_TypeDef *DMA_Struct 需要初始化的DMA结构体地址
//输 出：无
//返 回： 0 : 成功
// -1 : 失败
// -2 : 传输字节数超出范围(<0x0FFFFF)
//======================================================================
int DMA_Init(DMA_Struct_TypeDef *DMA_Struct)
{
if ((*DMA_Struct).DMA_BytesCount > 0x0FFFFF)
return (-2);
const DMAMUX_x_TypeDef DMAMUX_x = DMAMUX_x_GET((*DMA_Struct).DMAMUX_Source);
switch (DMAMUX_x)
{
case DMAMUX0:
SIM_SCGC6 |= SIM_SCGC6_DMAMUX_MASK;
break;
default:
return (-1);
}
SIM_SCGC7 |= SIM_SCGC7_DMA_MASK;
DMAMUX_CHCFG_REG(DMAMUXx[DMAMUX_x], (*DMA_Struct).DMA_CHn) = 0;
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) = 0;
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DCR_DMOD_MASK;
const DMAMUX_SRC_TypeDef DMAMUX_SRC = DMAMUX_SRC_GET((*DMA_Struct).DMAMUX_Source);
if (DMAMUX_SRC == DMA_SoftTrig)
{
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DCR_ERQ_MASK;
}
else
{
DMAMUX_CHCFG_REG(DMAMUXx[DMAMUX_x], (*DMA_Struct).DMA_CHn) |= DMAMUX_CHCFG_SOURCE(DMAMUX_SRC);
if ((*DMA_Struct).DMAMUX_Trig == DMA_Periodic)
DMAMUX_CHCFG_REG(DMAMUXx[DMAMUX_x], (*DMA_Struct).DMA_CHn) |= DMAMUX_CHCFG_TRIG_MASK;
else
DMAMUX_CHCFG_REG(DMAMUXx[DMAMUX_x], (*DMA_Struct).DMA_CHn) &= ~DMAMUX_CHCFG_TRIG_MASK;
}
//Source
DMA_SAR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) =
DMA_SAR_SAR((*DMA_Struct).DMA_Source.DMA_Addr);
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DCR_SSIZE_MASK;
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_SSIZE((*DMA_Struct).DMA_Source.Data_Size);
if ((*DMA_Struct).DMA_Source.Addr_INC == DMA_ADDR_INC)
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_SINC_MASK;
else
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DCR_SINC_MASK;
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DCR_SMOD_MASK;
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_SMOD((*DMA_Struct).DMA_Source.Addr_MOD);
//Destination
DMA_DAR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) =
DMA_SAR_SAR((*DMA_Struct).DMA_Destination.DMA_Addr);
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DCR_DSIZE_MASK;
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_DSIZE((*DMA_Struct).DMA_Destination.Data_Size);
if ((*DMA_Struct).DMA_Destination.Addr_INC == DMA_ADDR_INC)
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_DINC_MASK;
else
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DCR_DINC_MASK;
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_DMOD((*DMA_Struct).DMA_Destination.Addr_MOD);
DMA_DSR_BCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DSR_BCR_BCR_MASK;
DMA_DSR_BCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DSR_BCR_BCR((*DMA_Struct).DMA_BytesCount);
if ((*DMA_Struct).DMA_CycleSteal == DMA_CycleSteal)
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) &= ~DMA_DCR_CS_MASK;
else
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_CS_MASK;
if (DMAMUX_SRC == DMA_SoftTrig)
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_START_MASK;
else
DMA_DCR_REG(DMAx[0], (*DMA_Struct).DMA_CHn) |= DMA_DCR_ERQ_MASK;
//DMAMUX_CHCFG_REG(DMAMUXx[DMAMUX_x], (*DMA_Struct).DMA_CHx) |= DMAMUX_CHCFG_ENBL_MASK;
return (0);
}
