MobiFlight Community Support

Hi.

Basicly the "Relais" System was build to work with the LED ( Not Max7219) It is also not designed for Motors... Like a stepper MUST be initialised. (Else there is no Zero Position)

With the Relais Logic we will save a lot of Configs ( Battery Off) and with a second system for Lighttest ( parallel power line to all LED external of MF via Relais) we can do this, too.

So i think the low number of MAX7219 must NOT be done via Releas.... It can be done with software preconditions !

But SHURE !!! I know people report blanking is problematic in case of a bug.
Bet here i would say... We not need to find a way to do that with a relais like with LED.... we should simply solve the Bug so the Precondition Blank will work fine like in the past !

Looking again at this post, a power mosfet could switch the common ground of LED outputs.

That could emulate a "master battery" bus, with hardware limitations.

Paul

This is a super old thread but here is how I do some of this stuff. After talking with Pizman and some other folks on discord, and thinking for a while, I came up with this idea that seems to work well:

I have a circuit that uses a FET to control the GND side of all of my leds. So the FET output pin has a config that reads the panel backlight intensity from the simulator and sets the output on or off. And with PWM support on outputs, it can also adjust the brightness which is very nice for night flights, if you have separate panels like I do, each with their own backlights, they work in sync.

Each led is then connected normally to IO pins as outputs, but their GND is just routed via the FET. Since this basically emulates the battery bus like you have in a real plane, you just configure each led normally and you dont need to worry about battery power or anything else there, because that logic is split into the FET side and it just enables or disables all leds at once.

I also realized I need to have another circuit for warning lights GND "bus" because many planes seem to turn off panel backlights when panel light dimmer is turned to MAX, but warning lights naturally need to be at maximum brightness. So these need separate logic.