Add halfduplex to serial::config::Config and example

[dsmcfarl]

This allows the USART's to be used with serial devices that operate in a half-duplex mode (transmit and receive on one wire). An example was also added (serial-halfduplex) and has been tested with a NUCLEO-H723ZG board. It has also been tested with a Frysky RX4R RC receiver Smart Port interface.

[richardeoin]

Thanks for the PR! This looks really nice and I appreciate the explaination of the setup in the example.

In the existing HAL it was already possible to configure synchronous mode (3 wires!) by passing 3 pins during the initialisation. That then sets the CLKEN bit high here.

let mut usart6 = dp
        .USART6
        .serial((usart6txpin, usart6rxpin, usart6clk), ...);

According to the reference manual the CLKEN and HDSEL bits are mutually exclusive - so you can't set both at the same time. I think the HAL should return an error or panic in that configuration rather than just going ahead. Could you add a check and return Err() for this?

[richardeoin]

The CI should now pass

bors try

[richardeoin]

I would like to have this PR merged for the next release, so at some point I will make the change I described in my earlier comment. @dsmcfarl please let me know if that's a problem or you would prefer something else!

[bors]

try

Build succeeded:

• Rustfmt
• ci (1.62.0, stm32h743)
• ci (1.62.0, stm32h753)
• ci (1.62.0, stm32h743v)
• ci (1.62.0, stm32h753v)
• ci (1.62.0, stm32h747cm7)
• ci (1.62.0, stm32h7b3)
• ci (1.62.0, stm32h7b0)
• ci (1.62.0, stm32h735)
• ci (stable, stm32h743)
• ci (stable, stm32h753)
• ci (stable, stm32h743v)
• ci (stable, stm32h753v)
• ci (stable, stm32h747cm7)
• ci (stable, stm32h7b3)
• ci (stable, stm32h7b0)
• ci (stable, stm32h735)

[richardeoin]

Updated and rebased onto master

[richardeoin]

bors r+

[bors]

Build succeeded:

• ci (1.62.0, stm32h735)
• ci (1.62.0, stm32h743)
• ci (1.62.0, stm32h743v)
• ci (1.62.0, stm32h747cm7)
• ci (1.62.0, stm32h753)
• ci (1.62.0, stm32h753v)
• ci (1.62.0, stm32h7b0)
• ci (1.62.0, stm32h7b3)
• ci (stable, stm32h735)
• ci (stable, stm32h743)
• ci (stable, stm32h743v)
• ci (stable, stm32h747cm7)
• ci (stable, stm32h753)
• ci (stable, stm32h753v)
• ci (stable, stm32h7b0)
• ci (stable, stm32h7b3)
• Rustfmt

[dsmcfarl]

Just saw this and see you merged it. Looks great thanks!

…

On Thu, Feb 23, 2023 at 3:11 PM Richard Meadows ***@***.***> wrote: I would like to have this PR merged for the next release, so at some point I will make the change I described in my earlier comment. @dsmcfarl <https://github.com/dsmcfarl> please let me know if that's a problem or you would prefer something else! — Reply to this email directly, view it on GitHub <#408 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AASLPDUBMSYL5SZIBJAPXR3WY7G7VANCNFSM6AAAAAATOJ2WEQ> . You are receiving this because you were mentioned.Message ID: ***@***.***>