Hi DrTank
The cannon is not firing because your elevation stick is NOT travelling to its full extent. The trigger for fire is when the stick goes above +- 75% of range. Either increase the limits for the elevation channel on your stick OR assign a switch to say +120% of the elevation channel.
Have a look at hawkeye3guns post in the very topic just underneath yours (same issue - same solution)
viewtopic.php?f=148&t=867The VERY limited range of travel employed by Spektrum is one reason why these radios are great for aircraft but not so good for land vehicles. Similarly why the factory firmware on the TGY9X is better swapped for ER9X.
Land vehicles typically allow for switching of lights, firing of guns, movement of other parts. To be able to control all these functions the range of a channel must be wide so that each function can be assigned a particular part of the channel range. The wider the channel range the more functions. For example our Taipan protocol is this for CH3/ELE/GUN channel
-125% to - 110% Machine Gun 2
-109% to -76% Machine Gun 1
-75 % to + 75% Gun elevation
+76% to + 110% Standard cannon round
+111% to + 125% Armour piercing/high explosive round
Cheers
Kevin G