[MPC5777c] SDADC with using DMA

[hanryang]

Hello.

I'm trying to SDADC with using DMA for resolver Sin & Cos Signals.

So now I'm reffering to eTPURDCCUG.pdf with example codes (Example_MPC5777C-SDADC_eTPU_triggered_v0_0-GHS714 & Example_MPC5777C_DSPI_Master_TXRX_DMA_S32DSPower21)

eTPURDCCUG.pdf suggets three DMA channels are used – two channels to transfer the ADC data of Sine and Cosine signals, and one channel to transfer the HSRs.

I wanna use SDA[0], SDA[1] for Sin signal and Cos signal.

Sin signal - SDA0

Cos signal - SDA1

Now I'm using eQADC with DMA, below the source code is summary of DMA init for eQADC. 

---- No 1. summary of DMA init for eQADC ---

DMA_A.TCD[0].SADDR.R = (vuint32_t) &A_CQUEUEX0; //  Start Address

DMA_A.TCD[0].DADDR.R =  CFIFO_A0_PUSH;    //  Destination address

DMA_A.TCD[1].SADDR.R = RFIFO_A0_POP;      //  Start Address //

DMA_A.TCD[1].DADDR.R = (vuint32_t) &A_RQUEUEX0;//  Destination address

DMA_A.TCD[2].SADDR.R = (vuint32_t) &A_CQUEUEX1; //  Start Address

DMA_A.TCD[2].DADDR.R =  CFIFO_A1_PUSH;    //  Destination address

DMA_A.TCD[3].SADDR.R = RFIFO_A1_POP;      //  Start Address //

DMA_A.TCD[3].DADDR.R = (vuint32_t) &A_RQUEUEX1;//  Destination address

DMA_B.TCD[0].SADDR.R = (vuint32_t) &B_CQUEUEX0; //  Start Address

DMA_B.TCD[0].DADDR.R =  CFIFO_B0_PUSH;    //  Destination address

DMA_B.TCD[1].SADDR.R = RFIFO_B0_POP;      //  Start Address //

DMA_B.TCD[1].DADDR.R = (vuint32_t) &B_RQUEUEX0;//  Destination address

DMA_B.TCD[2].SADDR.R = (U32)&B_CQUEUEX1; //  Start Address

DMA_B.TCD[2].DADDR.R = CFIFO_B1_PUSH;    //  Destination address

DMA_B.TCD[3].SADDR.R = RFIFO_B1_POP;      //  Start Address //eQADC

DMA_B.TCD[3].DADDR.R = (U32)&B_RQUEUEX1;//  Destination address

---- End of summary ----

----- No 2. Construction of DMA init for eQADC -----

DMA_A.TCD[0].SADDR.R = (vuint32_t) &A_CQUEUEX0; //  Start Address

DMA_A.TCD[0].DADDR.R =  CFIFO_A0_PUSH;    //  Destination address

DMA_A.TCD[0].ATTR.B.SMOD = 0x00; //  Source address modulo

DMA_A.TCD[0].ATTR.B.DMOD = 0x00; //  Destination address modulo

DMA_A.TCD[0].ATTR.B.DSIZE = 0x02; //  Destination transfer size : 32 Bits

DMA_A.TCD[0].ATTR.B.SSIZE = 0x02; //  Source transfer size : 32 Bits

DMA_A.TCD[0].SOFF.R = 0x04; //  Signed source address offset

DMA_A.TCD[0].NBYTES.MLNO.R = 0x00000004; //  Inner "minor" byte count

DMA_A.TCD[0].SLAST.R = -16; //  last Signed source address adjust

DMA_A.TCD[0].DOFF.R = (vint16_t)0x0;    //  Signed destination address offset

DMA_A.TCD[0].DLASTSGA.R = (vint32_t)0x0; //  Signed destination address adjust

DMA_A.TCD[0].BITER.ELINKYES.B.ELINK = 0x00; //  Disable Channel Linking  Minor Loop Channel Linking Disabled

DMA_A.TCD[0].BITER.ELINKYES.B.BITER = 0x0004; //  Beginning "major" iteration count - Minor Loop Channel Linking Disabled

DMA_A.TCD[0].CITER.ELINKYES.B.ELINK = 0x00;    //  Disable Channel Linking  Minor Loop Channel Linking Disabled

DMA_A.TCD[0].CITER.ELINKYES.B.CITER = 0x0004; //  Current "major" iteration count - Minor Loop Channel Linking Disabled

DMA_A.TCD[0].CSR.B.BWC = 0x00; //  Bandwidth control :  No DMA Stalls

DMA_A.TCD[0].CSR.B.MAJORLINKCH = 0x00; //  Major Channel number

DMA_A.TCD[0].CSR.B.MAJORELINK = 0x0; //  Major Channel Link : Disabled

DMA_A.TCD[0].CSR.B.DONE = 0x00; //  Channel Done

DMA_A.TCD[0].CSR.B.ACTIVE = 0x00; //  Channel ACtive

DMA_A.TCD[0].CSR.B.ESG = 0x0;

DMA_A.TCD[0].CSR.B.DREQ = 0x0;

DMA_A.TCD[0].CSR.B.INTHALF = 0x0;

DMA_A.TCD[0].CSR.B.INTMAJOR = 0x0;

DMA_A.TCD[0].CSR.B.START = 0;

----- End of construction of DMA init for eQADC-----

------ No.3 Construction  of SDADC_init from Example code -----

void SDADC2_Init(void)
{
/* for comments see SDADC1_Init */

SIU.SDCLKCFG.R = 0x0000003F;
SDADC_2.MCR.B.EN = 1;

/* TRIGSEL = 0101b = 5 = eTPU_A23 */
SDADC_2.MCR.R = 0x00001593;

SDADC_2.CSR.R = 0x0;
SDADC_2.OSDR.R = 0xFF;
SDADC_2.FCR.R = 0x107;
SDADC_2.RSER.R = 0x00000001;
}

------ End of construction SDADC_init  from Example code ------

*Question

1. how do I apply SDADC with using DMA for Sin - SDA[0], Cos - SDA[1], HSR ?

(Based on above eQADC code)

2. Can I perform DMA initialization for SDADC using the same structure as the DMA source code configuration for eQADC as in No.2 above?

(If not, Please let me know how to configurate)

3.To initialize SDADC using DMA, Is it correct to configure SDADC initialization in the same way as example code 3 above?

(If not, Please let me know how to configurate)

Thank you for always helping me.

MPC5777C 

[davidtosenovjan]

According sketch in shows using differential inputs i.e. SIN by one pair of inputs, COS by another pair.

In comparison to eQADC - SDADC does not use any commands as you have in the TCD above. You will only need DMA transfers for results' draining.

Some general words to SDADC:
SDADC is targeted to high-precision, moderate input bandwidth AC signal processing (knock detection/in pressure cylinder control).
Once enabled the SDADC keeps running. There is no “Single conversion mode”. This requires converted data to be continually drained by DMA or ISR. The digital nature of the SDADC means that there is a propagation delay as the data is clocked through the internal digital filters. This has to be taken into account at startup or at any channel mux change. This latency means that the SDADC is not well suited to some applications including motor control. When used in an AC sampling application it is likely that each SDADC will have to be dedicated to a particular input rather than switching the input channel.
SDADC offers higher conversion accuracy (16-bit result).

SDADC is always combined with other type of ADC, on this device it is eQADC offering advanced triggering and channel multiplexing capability (on other MPC57xx device SDADC is supplemented by SAR ADC).

[hanryang]

Thank you for your answer.

I'm a beginner level so I couldn't understand much of your explained without exmaples...

Can you show me how should I configure SDADC with using DMA?

I want to configure DMA configuration as shown in the table below.

I want to use SDA0 and SDA1 channel for Sine ADC FIFO DMA channel and Cosine ADC FIFO DMA channel, but I'm already using TCD[0] and TCD[1] for eQADC.

If I want to use SDA0 and SDA1 channel for DMA Channel, How should I do?

[davidtosenovjan · Accepted solution]

I see. This table is described quite straightforward. Use recommended values.

For SDADC following channels is supposed to be used (eDMA_B):

For HSR, you may use any channel.