• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 2 answers
  • Subscribers 33 subscribers
  • Views 151 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.

Original question:

TCA6408A-Q1: Can we use only 2 GPIO pin as External Input?

TCA6408A-Q1: GPIO pin can be used as INT

Jitendra kumar
Prodigy 90 points
Part Number: TCA6408A-Q1

I have some concern regarding with i/o Expander TCA6408AQPWRQ1 INT Pin.

Now, I want to add above 2 Switch on GPIO as input with this Expander IC and connect it with this Deserializer. for same i have some questions.

Q1. At which condition of this IC, INT pin will be toggle ?? 

Q2. Can we use this IC's GPIO (P0-P7) pin just like as Interrupt Pin (without polling method)??

  • 0
    Guru 259160 points

    The /INT pin activates when any input pin changes. So you will get a signal when a switch is closed, or opens, or bounces; you have to read the input port register to find out what happened.

  • 0
    TI__Mastermind 20581 points

    Hey Jitendra,

    To add on to Clemens' response, the GPIO ports of this device are configured as inputs upon startup and can be used with external INT. You would need to perform an input register read when you see the INT pin being assessed. (Note that polling method would not be used since the I/O expander is a classified as a slave device). 

    Regards,

    Jack