SUMD serial protocol support

[mikeller]

Is it possible to get support for the SUMD (https://www.scribd.com/document/2053591 ... 062012-pdf) serial protocol added to er9x / ersky9xr? The protocol spec looks simple enough, and I'd be happy to help with the implementation, but I couldn't find recent sources.

[MikeB]

The most recent sources are here: https://github.com/MikeBland/mbtx/tree/next (in the next branch).

Is SUMD a protocol for the transmitter, the document says "The data stream is generated by HoTT receivers" ?

Mike.

[mikeller]

Is SUMD a protocol for the transmitter, the document says "The data stream is generated by HoTT receivers" ?

Looks like it can be used on both sides of the link, or at least openLRSng has it implemented on RX and TX side:

https://github.com/openLRSng/openLRSng/ ... #L562-L603

[Kilrah]

It is only meant to be used between receiver and servos, and as such can't carry the useful things one would want to send to a module. There are better things for that.

OpenLRSng has that tendency of taking receiver output formats as input which I'm perfectly OK with when used for the originally intended purpose (a wireless relay using said receivers receiving info from their "native" module), but for direct radio-module communication there are better choices, and instead of asking radios to send inappropriate formats OpenLRSng should really add support for the appropriate ones.

[mikeller]

The most recent sources are here: https://github.com/MikeBland/mbtx/tree/next (in the next branch).

I got the sources, thanks.

Also, I have implemented basic support for the MULTI protocol in openLRSng: https://github.com/openLRSng/openLRSng/pull/117

This comes with the drawback that, when it is enabled, the only serial port on the openLRSng module, that is also used for telemetry, is forced into 100000 8E2 mode. In order to make it possible to use serial TX and telemetry at the same time, the controller firmware will have to be amended to make it possible to either manually select speed / mode for telemetry, or make it possible to have it set to the serial TX settings.

What do you think about this?

...instead of asking radios to send inappropriate formats OpenLRSng should really add support for the appropriate ones.

I still don't agree that any of these protocols are 'inappropriate' as a digital replacement for PPM. After all, the main purpose of these protocols is to transfer rc commands with short lag times and no inaccuracies, and they all do a good job of that.

[MikeB]

In ersky9x, if you select MULTI as the protocol, then the telemetry input is also set to 100kbaud and 8E2.

Mike.

[mikeller]

In ersky9x, if you select MULTI as the protocol, then the telemetry input is also set to 100kbaud and 8E2.

Nice one. That's exactly what is needed, no change required then. It's like you're reading my mind.

[mikeller]

Confirmed working in a test flight with latest ersky9xProvR219t_music. openLRSng now can support a fully digital rc command / telemetry setup with ersky9x. Good work, @MikeB!

I found that on my 9XR Pro, after a while, audio output cut out, and I had to restart it to get audio back to work. Is there an older version that has the changes to support 100kbps, 8E2 for telemetry, but does not have the changes to the audio subsystem?

[MikeB]

You could try the version in "ersky9xProvR219i.zip". I'm not aware of any problems with the audio in the latest test version ('R219t_music').

Mike.