Variant.h for RUMBA32

[MagoKimbra]

Please enter the TIMER_SERIAL define in variant.h of rumba32.
If the SoftwareSerial.h library is included, as is the case with the TMCStepper library, SoftwareSerial takes the timer 7 for the STM32F446 processor which is the same one used by the servo and in fact no longer works.
I put #define TIMER_SERIAL 8 in variant.h so the servo works, but I don't know if the SoftwareSerial library works, it should be verified ...

[fpistm]

Hi @MagoKimbra
in this case you could provide a PR.
This is well explained here:

Arduino_Core_STM32/libraries/SoftwareSerial/src/SoftwareSerial.cpp

Lines 42 to 51 in 2f1fd8e

	#define HALFDUPLEX_SWITCH_DELAY 5
	// It's best to define TIMER_SERIAL in variant.h. If not defined, we choose one here
	// The order is based on (lack of) features and compare channels, we choose the simplest available
	// because we only need an update interrupt
	#if !defined(TIMER_SERIAL)
	#if defined (TIM18_BASE)
	#define TIMER_SERIAL TIM18
	#elif defined (TIM7_BASE)
	#define TIMER_SERIAL TIM7
	#elif defined (TIM6_BASE)

So I guess there is no TIM18 for F446 and then TIM7 is used.

[MagoKimbra]

Yes, TIM18 not define for STM32F466 and use the first TIM7.
I tried to put the define in my HAL firmware, but it is not seen by SoftwareSerial.cpp.

[fpistm]

Don't know your HAL firmware but if set in variant.h this should be ok

[MagoKimbra]

Yes yes in variant.h the servo works perfectly. I tried to put the define in my firmware which includes the TMCstepper.h library which in turn includes the Softwareserial.h library, but unfortunately the define is not seen, I said this.

[fpistm]

ok.
Other way is to use build_opt.h or maybe the hat_conf_extra.h.

[fpistm]

@MagoKimbra
which timer you want for TIMER_Serial per default ?

[MagoKimbra]

TIM9. Thank's.
I use TIM2 for stepper, SysTick for the rest. There are still TIM5 32bit, TIM3, TIM4, TIM10-TIM14 at 16bit for other things.

[fpistm]

Well, I will not modify the variant as this will fix it for all users and they do not want necessarily to use this one.
In your case you have to add hal_conf_extra.h with
#define TIMER_SERIAL TIM9

[MagoKimbra]

Where i add hal_conf_extra.h??? in Myfirmware or in library STM32???

[fpistm]

When using Arduino IDE, simply adding it at sketch level works.
While the file is in the include path this will work.