Setting up a servo output as GPIO to control relay remotely?

Hi there!

I’m using the Speedybee F405 WING FC, which as a bunch of servo/PWM outputs - and I’m trying to configure one of them to control a relay, but it doesn’t seem to work.

What I’ve tried is:

Defining servo 9 as GPIO

Setting the RELAY_PIN2 to 58, after checking the manual to find the GPIO pin for servo 9

I’ve set up RC10 OPT to control Relay 2

And then I wrote all params etc, and rebooted the device - but the relay isn’t being triggered. I verified that RC10 is indeed getting triggered using the radio calibration, and also used a voltmeter to verify that nothing changes, so I’m thinking I’ve done something wrong, or missed a step. I’m thinking it’s most likely when I defined the pin as 58 for relay 2, maybe that corresponds to some other internal option?