Using LCD pins for UART, and the dts configurator

[Doug Springer]

Hi,

We are trying to use CTS/RTS for uart4 using LCD12/LCD13. The TI pin configurator says these pins are busy by the boot mode pins.  However, we see the am335x-moxa-uc-8100-common.dtsi is using LCD pins for UART2.

Is there some reason we cannot use the LCD pins for their appropriate functions AFTER the board has booted?

We understand that anything connected before boot has to retain the respective voltage levels until boot, but after boot, we should be able to use them?

• This topic was modified 1 month, 3 weeks ago by Doug Springer.

[Neeraj Dantu]

Doug,

Yes, SYSBOOT configuration is latched at power on reset. After that, you can use these pins for other functions. Some Beagleboards and OSD3358-SM-RED use these pins for LCD interface.

If you are getting a ‘busy’ status, that may be because they are being used for some other interface elsewhere in the device tree. I would review the device tree to see if there is any pinmux other than the UART being setup for these pins.

Best,

Neeraj

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