• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 78 subscribers
  • Views 558 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

MSP432P401R: MSP LaunchPad and AMC Isolation amplifier

Adi Selimovic
Intellectual 560 points

Part Number: MSP432P401R

I am implementing 3-phase energy metering with requirements to have data storage up to one month, wireless and web browser as well, accuracy for U and I measurement 0.2% (>12 bits of resolution).
My research has ended up with 2 possibilities:
  • MSP432P401R LaunchPad (14 bit ADC, no SD slot)
  • MPS430FR5994 LaunchPad (12 bit ADC, with SD slot)

As I want to have isolated measurement, I decided to use either AMC1304 (output is a bitstream) or AMC1301 (analog output). Therefore I can combine these with previously mentioned LaunchPads. In that regard, questions are the following:

  1. In a case I choose MSP432P401R LaunchPad together with AMC1301, how challenging is to implement external SD Slot and provide data storage?
  2. In a case I choose MPS430FR5994 LaunchPad together with AMC1304, are there possibilities to process data correctly due to a fact that AMC1304 requires SD filters which this LauncPad doesn't have?
  3. If you have any suggestions, I would be very thankful.
Thank you in advance,
Adi 
  • 0
    TI__Expert 8510 points

    For the MSP432 case, I'd suggest looking at the FATSD example, which reads/writes to an SD card using a SPI interface. There is a specific TI driver for doing this, called SDSPI, which is referenced in the source. Details of this API can be found in the TI Drivers API reference in Resource Explorer.

    For the AMC1304 case, you would have to recreate a Sigma-Delta demodulation filter in software, which means you would be sampling the AMC1304's data output at a fairly high frequency while providing a  continuous output clock to that device from the MSP430. I don't think you could bit-bang this interface (the CPU would be high utilized unless your clock frequency is relatively low). It's conceivable you could use a SPI to continuously stream data into the MSP430 as long as you don't miss any data-ready interrupts and thus lose data bits.

    -Bob

**Attention** This is a public forum