PROCESSOR-SDK-AM335X: UART single wire interface

Durga Prasad Reddy B

Hi,

My requirement is like, I have to use single wire interface to communicate with slave device.

I want to know how to configure the UART single wire interface i.e(using single line for Tx and Rx)? Whether it is possible in Beagle bone black in Linux.

Is there any Linux driver available to support UART single wire interface?

Thanks & Regards,

Durga Prasad.

over 7 years ago

0 Biser Gatchev-XID over 7 years ago

TI__Guru**** 393215 points

This mode is not supported by the AM335x UART.

0 Matthijs van Duin over 7 years ago

Mastermind 8040 points

My suggestion would be to connect both rxd and txd of one of the beaglebone's UARTs to this interface of the device, with a series resistor on txd. A good value for the resistor depends on the electrical characteristics of this interface on the slave device: I would suggest at least 10 times its output impedance (when transmitting) but less than 1/10th its input impedance (when receiving).

Keep in mind that this arrangement means you will receive all data transmitted on the wire, both the device's and your own.

0 Durga Prasad Reddy B over 7 years ago in reply to Matthijs van Duin

Intellectual 450 points

If I make the above setup ready. Is there any driver already present to support this in Linux ?

0 Biser Gatchev-XID over 7 years ago in reply to Durga Prasad Reddy B

TI__Guru**** 393215 points

The standard UART driver should work, though you should keep in mind what Matthijs posted above:

"Keep in mind that this arrangement means you will receive all data transmitted on the wire, both the device's and your own."

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PROCESSOR-SDK-AM335X: UART single wire interface