alarm based on garmin edge + DI2

Hello every body, 

I would like to know if it possible to creat an app in connect IQ able to activate alarm tone of garmin edge (530) with long push in button of di2 to alert pedestrian for exemple. 

I already creat datafeild with sdk garmin (https://apps.garmin.com/fr-FR/apps/ba61b904-0bc1-4572-b497-fea32eca59f7) but I don't find any instruction to du that. 

Maybe it's imposible? 

Jérémy