• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 81 subscribers
  • Views 191 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.

TMS320F28065: Unused GPIO pin

Ryo Akashi
Expert 8950 points
Part Number: TMS320F28065

Hello experts,

Could you tell me what should I do for below unused pin in TMS320F28065PZPS?
-51 GPIO18/SPICLKA/SCITXDB/XCLKOUT
-52 GPIO17/SPISOMIA/Reserved/TZ3
-55 GPIO16/SPISOMIA/Reserved/TZ2
-64 GPIO19/XCLKIN/SPISTEA/SCIRXDB/ECAP1

From datasheet P12, all of GPIO pin seems to have internal pull-up resistor which can be selectively enabled or disabled on a per-pin basis.
So, should we enable internal pull-up resistor and left be unconnected?

Thanks and best regards,
Ryo Akashi

  • 0
    TI__Mastermind 41385 points

    Akashi-San,

    Great question. If GPIOs are not needed they can be left unconnected. 

    If the GPIO is configured as an output, no other configuration is needed.

    If the GPIO is configured as an input please make sure that the internal pull up is enabled. For many pins this is the default option. When the GPIO is configured as an input with no driver it can drift to a mid-rail voltage, this can increase device current consumption. Enabling the internal pull up prevents this by ensuring the voltage stays at ~3.3V.

    The default state of the pull up register is documented in the register description section for GPAPUD.

    Regards,
    Cody