ADS8910B: How does MSP432E401Y read 18-bit data of ADS8910B via Legacy SPI

Ming Liao

Part Number: ADS8910B
Other Parts Discussed in Thread: MSP432E401Y

Hi,

To read ADS8910B’s 18-bit data, DSS of SSICR0 register of MSP432E401Y is better to set at 0x8 (9-bit data), right?

However, For MSP432P4xx series, if the data size in SPI mode is normally set at 8-bit with 18 SCLK clocks, the first 2 of 8-bit data are no problem to be received, and is UCRXBUF OK to catch the last 2-bit data?

If possible, would you please share the sample codes of how MSP432 MCUs reads the 18-bit data from ADS8910B?

Thanks,

Ming

over 5 years ago

0 Sandeep Kasargod over 5 years ago

TI__Expert 4405 points

Ming,

Hi!!

You could setup the SPI module for 3 sets of 8-bits each within a common CS\. This will generate 24 SCLKs and the UCRXBUF would catch two valid bits and 6 invalid bits in the last set.

Unfortunately, I do not have sample code for an MCU interfacing with the ADS8910B that I can share with you.

Regards,
Sandeep

0 Ming Liao over 5 years ago in reply to Sandeep Kasargod

Intellectual 450 points

Hi Sandeep,
From you reply, I guess the best way for sending 18 SCLKs to ADS8910B is to use MSP432E401Y with 9-bit data size.

Thanks.

Ming

0 Sandeep Kasargod over 5 years ago in reply to Ming Liao

TI__Expert 4405 points

Ming,

You are right.

Two 9-bit frames would definitely work better.

I was under the impression that it needed to be in multiples of bytes. But the MSP432E401Y frame size can be anywhere between 4 and 16 bits wide.

Thanks for pointing this out.

Regards,
Sandeep

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ADS8910B: How does MSP432E401Y read 18-bit data of ADS8910B via Legacy SPI