• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 30 subscribers
  • Views 131 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.

PGA900: Inquiry Regarding PGA900 Output options

Dankim
Prodigy 40 points
Part Number: PGA900

Hello,

I have a technical question regarding the PGA900.

I want to use the PGA900 to output calibrated sensor values via UART. While I have confirmed that the PGA900 supports various output options as listed below, I would like to verify if UART output is also possible.

Output options:

  • Ratiometric and absolute voltage output
  • 4- to 20-mA current loop interface
  • One-wire interface (OWI) over power line
  • PWM output
  • Serial peripheral interface (SPI)
  • Inter-integrated circuit (I2C)

Thank you for your assistance.

Best regards,

  • 0
    TI__Guru** 113765 points

    Hi Dankim,

    You have basically listed the output options from the front page of the datasheet.  You can find additional information within the datasheet that also describes the PGA900 operation.  Included in the communication is the UART function.  UART communication takes place on dual function pins with SPI, so you can use UART or SPI but not both.  By default the pins are configured for SPI.  Also, the UART functionality is disabled on device power-up.  For additional information see section 7.3.20.2 in the datasheet.  So to be able to use the UART functionality you would need to enable the UART interface through a different interface first, or in your application firmware code turn on the interface.

    In addition, even though you may be able to communicate with PGA900 using a different interface (such as I2C), the only thing you can do is read and write registers.  There is no application firmware installed in the device.  You will need to develop code for the M0 processor.  So being able to communicate with the PGA900, is only a small part of the requirements needed to truly utilize the device.

    Best regards,

    Bob B

  • 0 in reply to Bob Benjamin
    Prodigy 40 points

    I understand that I need to write application firmware code to operate the UART interface.

    I have additional questions.

    My application is for a pressure sensor. I would like to know if I need to create the logic for temperature compensation of the pressure sensor myself. I do not have a verified and certain idea for temperature compensation.

    Ideally, I would like to apply a compensation logic provided by you to complete the calibrated sensor output, and then only write the application firmware code for outputting the sensor values via UART.

    Is this method possible?

  • 0 in reply to Dankim
    TI__Guru** 113765 points

    Hi Dankim,

    There is an example firmware project that contains information and the process for capturing the conversion data and then compensating to a 2nd order polynomial equation.  You will need to compute the coefficients during a calibration process and store the values to the PGA900 EEPROM for the firmware to use while compensating.

    Best regards,

    Bob B