Help with ELRS /Crossfire

Using ELRS as the RC input.
Connected to RX6/Tx6 on Matek H743 wing.
The RC connection shows in the Setup Radio calibration window, but it is really slow and jerky. It acts like its only updating once a second or so
With servos connected in manual mode its is also really jerky…
To try and fix this I set:


It made absolutely no difference.
Is there some way to show the rate of recieved RC frames?
Should I slow it down ELRS trys to send data at 500Hz.

Thanks for any help!

First of all, normally the response of ELRS is as instant as remote control can be, whatever the data frequency.

Second, ELRS loves DMA-enabled UARTs. If I remember correctly, Rx6/Tx6 on Matek H743 boards is not DMA-enabled. With me, however, ELRS works just about right even on non-DMA ports, but it has been known to cause problems in the past.

I recall someone having the same symptoms, but so far I cannot remember the exact cause. If I eventually find this out, I will post it here.

Setting BRD_ALT_CONFIG=1 fixes it otherwise UART is not really bi directional.

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