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Interfacing between TMS320C6713 and ADS8345 by using McASP

Started by ShaikSajida 3 weeks ago1 replylatest reply 3 weeks ago39 views

Hi,

I am using a TI DSP C6713B.

I want to connect the McASP1 to ADC ADS8345.

My aim is to get serial (or in TDM format) data from 8-ch microphones that are connected to ADS8345.

I am trying to program the ADC ADS8345 using McASP and have a couple of questions.

1) Is it requred to program the ADS8345 (precision A to D Converter) using McASP?

2) After initialization of McASP, I am not able to see clock and framesync (probed on the respective pins

3) After debugging the code in CCS V5.5, I found that the execution stoped at while loop as shown here

/*---------------------------------------------------------------*/
/* Take transmit and receive state machine out of reset*/
/*---------------------------------------------------------------*/
MCASP_enableSm(hMcasp, MCASP_XMTRCV);
while(!(MCASP_FGETH(hMcasp,GBLCTL,RSMRST) & MCASP_FGETH(hMcasp,GBLCTL,XSMRST)));

(4) Can anyone please help me to solve this problem. 

Thanks,

Sajida

[ - ]
Reply by timburnettOctober 31, 2019

I have used a McASP before, but not on that particular processor. McASPs are extremely configurable, and I found I had to play with the settings quite a bit in order to get the desired results. 

I was using the McASP to talk to an audio ADC, which natively supports I2S and TDM data transfers. Your general purpose ADC only supports SPI transfers (!CS must be low to enable the shift register). I think you might be able to get it to work with a McASP in I2S master mode, since the left channel will correspond to framesync/!CS low. The right channel would be garbage, since the ADC would be deselected during that time slice. Your SPI transfers to the ADC would be passed over the left channel as well, with nothing useful on the right channel. 

It might be a lot easier to get working with the SPI peripheral instead, or using an audio ADC, just my 2 cents.

Regards, Tim