Found the issue... One of my new modules were using hardware i2c... Rather than soft i2c. If i remember correctly theres a hardware bug isnt there?
Anyway moving onto softwire fixed it!
Updated question, How to set PA15 to GPIO Output, and PWM questions...
Re: Updated question, How to set PA15 to GPIO Output, and PWM questions...
Just a dogs body developer, mostly making props and stuff...
Re: Updated question, How to set PA15 to GPIO Output, and PWM questions...
oh well, i'm getting a little rusty about this too 
i remembered once that i configured a function (likely a timer) and i see 'no outputs'.
That is on a stm32f4x1, it turns out some pin mapping i.e. AFIO function selection needs to be configured.
That is beyond simply setting a gpio as AFIO output and enabling the timer.
But i'd guess the codes should have 'mapped' that gpio e.g. in the TimerX.init() call.
And worse, i think some of the 'mapping' setups between F103 M3 vs F4x1 M4 is after all different.
In addition, that setOverflow(), I think affects the *update event* i.e. the full period.
and setCompare() affects the *capture compare register*, and that this is for the particular channel. i.e. the pwm duty cycle,
but 'Overflow' is the period and is shared by all channels.
keep the ref manual rm0008 handy while working these things, at least it becomes clearer trying to figure things out.
i remembered once that i configured a function (likely a timer) and i see 'no outputs'.
That is on a stm32f4x1, it turns out some pin mapping i.e. AFIO function selection needs to be configured.
That is beyond simply setting a gpio as AFIO output and enabling the timer.
But i'd guess the codes should have 'mapped' that gpio e.g. in the TimerX.init() call.
And worse, i think some of the 'mapping' setups between F103 M3 vs F4x1 M4 is after all different.
In addition, that setOverflow(), I think affects the *update event* i.e. the full period.
and setCompare() affects the *capture compare register*, and that this is for the particular channel. i.e. the pwm duty cycle,
but 'Overflow' is the period and is shared by all channels.
keep the ref manual rm0008 handy while working these things, at least it becomes clearer trying to figure things out.