• State
  • Locked Locked
  • Replies 2 replies
  • Subscribers 97 subscribers
  • Views 3723 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

Serial UART port using GPIO pins

Arul
Prodigy 205 points

Hi,

I am using AM17xx ARM processor of TI.

I have used all the 3 UART ports.(ie., To be precise, I have only used UART0 as a serial port. UART1 is used as CONSOLE and UART2 Tx pins clash with SPI0 Chipselect pin (which is used for flash).

Hence, I require another serial UART port. Is it possible to use GPIO pins and configure as UART3 ? (I need to access this UART from user space).

Please provide me the way to use platform_device code to create a new serial port.

Please help me on this regard.

Thanks,

Arul

  • 0
    Guru 26430 points

    I don't think one exists. Not that I can see in mainline kernel. There are "bit bang" I2C and SPI drivers but I think in those cases, they can can get away with it because of their synchronous nature. Any jitter is the serial clock is allowed. I have doubts a UART bit bang driver could shift out regular enough. No clock signal to correct for jitter. Vaguely remember 5% being the clock jitter allowed. Maybe a USB solution? An external UART controller on EMIF-A?

  • 0 in reply to Norman Wong
    Mastermind 7395 points

    From what I saw, UART2 TXD is not mapped with SPI0, but with SPI1...