As long as you can mix 2 or more channels to the throttle channel, you can do anything with that XIAO... you can use a toggle switched channel to initiated the cold start fast idle sequence... build tank pressure, increase the solenoid duty cycle for cold enrichment, and increase engine idle rpm... With the 18SZ I can use the throttle channel as a throttle position reference only, I have to sacrifice the channel output without a servo connected, and then mix channels to control the throttle servo, and fuel mixture... and then mix in another channel to control the air pump... and then use a conditional mix to initiate some sort of start up sequence based on the rpm and cylinder head temp, etc, but I'm limited to what the futaba telemetry can provide, so I would have to resort to sensory inputs directly into the MCU.