Interfacing (DSI, CSI, I2C, etc.) • Re: CM4 UART RTS - Unexpected Behaviour

Adding the ctsrts override to the UART overlay only configures the pins for RTS and CTS. It does not enable handshaking or the RS485 mode.

Enabling RS485 via RTS requires the request to be made to the kernel - https://www.kernel.org/doc/html/latest/ ... the-kernel. Does the library you're using do so?

Hi,

Thanks for getting back to me so quickly!
I'm not sure whether the library does or whether it can be configured to do so, I doubt it unfortunately.
Are the SER_RS485_ENABLED and SER_RS485_RTS_ON_SEND flag bits used to put the UART into half-duplex RS485 mode?
Can these be set at runtime, or can they be set in the kernel configuration?
If so, how would I go about setting them please?

The Modbus library that I linked is just being used for testing purposes, we have a custom .NET application for driving the busses in operation.
Can the UARTs be correctly configured for RS485 operation via .NET?

Many thanks,
Adam

Statistics: Posted by AdamWTracerco — Tue Jan 21, 2025 9:26 am

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