HAL #8: HowTo - Timer PWM

In this Tutorial im showing how and STM32 Timer ( TIM ) works, and how to use it.
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Thanks.
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[@borakavaklioglu4258]

This is the first tutorial that actually worked for me. You are amazing!

[@Weblearning1]

Yay! Thank you!

[@slip0n0fall]

Important to note that the Prescaler (and Period) get a '1' added to them (so a setting of 0 means a prescaler of 1, or no scaling)

[@ahmedladhibi6893]

Simple and clear ! best explaining so far ! thank you ! now a question how do we change the duty cycle and the frequency from the code

[@naasikhendricks1501]

I think a Free RTOS training module will be cool as you explain the essential details well.

[@Weblearning1]

It's also on the To Do list...

[@burhanmuhyiddin4372]

Your tutorials are just perfect. Thank you very much :)

[@Weblearning1]

Thanks for this

[@offensivebias3965]

Thank you for sharing your knowledge

[@englishman_i]

Everyone is looking forward to the next video!

[@Weblearning1]

Thanks.

[@alexandern8671]

Good video, thanks. I have not used Cube5 for timers yet but in Cube4 the prescaler and period values equated to the set value +1. I.e. to divide input frequency by 1000, one needed to set the register value to 999. Did Cube5 change this to be more intuitive?

[@filipenicoli_]

This behaviour is not due to CubeMX, but rather internal implementation details. You can find the Prescaler equation on the Timer Cookbook PDF from ST. There's also an image explaining the reason for the adjustment on auto reload register. Basically, when the timer reaches the "Pulse" value (CCRx), it immediately changes the output, but it waits one timer counting cycle to reset once reaching the auto-reload value (ARR). Thus, you should subtract 1 from ARR and from the Prescaler value, but not from Pulse.

[@sudhansumtripathy]

sir needs some clarification at 2:03 s of video, in 1 sec we get 1000 pulse , do you want to say that the pulse is high for 500 and low for 500, or for 1 complete cycle is 1/1000 =0.001

[@trinendragade7640]

This tutorial helps me a lot Thank you so much brother

[@Weblearning1]

Happy to help

[@stm32user]

Nice, but how to change the duty cycle ?. shall we increase the 500 while running ?

[@Weblearning1]

Yes. The best way is to play with these parameters and see what happens.

[@LoveTheFactory]

I wish BlueNRG-2 was STM32 so CubeMX could be used. Is there any way to leverage PWM on STEVAL-BCN002V1's RGB LED(s) ? Maybe with MFT2_TON & TOFF in PWM_config.h that includes BlueNRG1_mft.h in Micro_Hello_World project of DK 1.0.9 ? Or, software ones on PWM2-4_PIN defines ? Thanks for your awesome videos... They are VERY well done and we are very appreciative. :-)

[@mohamedfaroukbouklihacene819]

hi! thank you for the video! i want a 200khz pwm output and a i have set the internal clock to 8Mhz so i set the prescalar to 40 to have a prescalar output 200khz and when i put 200000 in the ARR(counter period) box it is impossible and the same thing with the CCR(pulse) box please help!

[@abdelazeemhassan3701]

AMAZING

[@ESEben10]

is there a formula that links the system's clock, presclaer,counter period and the required time in seconds? How should I obtain a period of 0,2s? Thanks for the video.

[@Weblearning1]

Have a look at this: www.emcu.eu/stm32-measure-time-period-and-frequency-of-a-signal-using-the-timer/

[@dimitris_g5651]

Hi can you tell me how what usb osciloscope are you using and how to set it up?

[@Weblearning1]

Have a look at one of my older videos that I do a review on the USB oscilloscope.

[@Guty28]

@@Weblearning1 Cant you just put the link?

[@MultiPantero]

Hi, probably its very basic stuff, but if I wanna generate a Burst Signal, will be posible using that timer?

[@Weblearning1]

Yes you can. Have a look at examples with STM32 IR, its the same thing.

[@TheRainHarvester]

How does one edit code using this method? Do you get to save all your menu settings for each timer you setup? (Ex. What if a year from now, I have my code but want to change the pin#/timing etc. But I don't remember the cube Mx stuff I setup that generated the code. ) Just curious. Thanks for the video.

[@Weblearning1]

Well, first it's best to save all you project in one place and the cube IOC file in the same place. if you still can't find the file, the you can read and see all your settings in the main.c file or peripheral files depends how you set it. See the movie that I made on who the cube generate the code.

[@luizazeredo5197]

Traduzindo e entendendo o código, obrigado por compartilhar conhecimento (Brasil)

[@НиколайКрасиков-ы8й]

Hello, which USB Oscilloscope do you use, please link ali and other? Where can I get such an Oscilloscope/Spectrum link for it?

[@Weblearning1]

I have 2: 1. Rigol 4 ch color scope that i have. I made a video on how to fix it. kzbin.info/www/bejne/kGOxeoyFZsyIgJI 2. A smaller and simpler one that I use for my videos: kzbin.info/www/bejne/qp6pZnVsosmlgrs

[@MrRonychakraborty]

you should also tell how to change duty

[@noithugian494]

can you use PWM + timer + DMA to generate DAC at STM32f103c8 ?

[@Weblearning1]

Yes you can. You use a block of data and you set the DMA to push every x time to the PWM. May be you can considerer subscribing to the channel?

[@cronnosli]

Hi, What I have understood from your example is that you set the frequency in CubeMX. There is a way to change the frequency while running. Let say that I want to modulate several frequencies from 30HZ up to 32MHZ, it is possible?

[@Weblearning1]

Yes. With the STM32 you can change almost everything from the code without resting the device. Just write to the registers again and that's it.

[@cronnosli]

@@Weblearning1 I'm still a newbie at STM32, there is any howto about writing to registers ?

[@poonamjangid01]

@3.41 in channel 1, no pwm option is available. I am using stm32f103c8t6.

[@Weblearning1]

Try a different channel, it should all work the same way.

[@MichasRichter]

Will this be applicable to the proposed 7S battery holder PCB with stm32 as BMS?

[@Weblearning1]

Yes, it can. But I didn't get almost anyone that what's to contribute to do this, so it looks like I will drop it for now.

[@baslinjames7714]

In the end of the video, the waveform was displayed and max voltage was around 3..can i increase or decrease that voltage level with the settings in cubemx?

[@Weblearning1]

No, the PWM is only 1 and a 0 of your voltage. You can use a Low pass filter and depending on the frequency, you can make it as a DAC. There are also other ways, with more GPIO and resistors as voltage dividers.

[@vladik8843]

increase and decrease voltage ? Man you need to start learning some basics. First step is to find out what PWM is..

[@abdelhakimazzouzi3371]

Thank you very much!

[@Weblearning1]

You're welcome!

[@leezanvlog8548]

hi, it's very usefull i see you use oscilloscope/spectrum analyzer software, can you give me link to download ?

[@Weblearning1]

I use a low cost one, see my video: kzbin.info/www/bejne/qp6pZnVsosmlgrs

[@abutaymiyyahlectures]

i want to buy an oscilloscope but its too expensive, i could buy a usb oscilloscope instead, but i dont know which to buy, any recommandations?

[@Weblearning1]

Did you end up buying one? Have a look at the video I made on the USB OSC that I have.

[@abutaymiyyahlectures]

@@Weblearning1 nope i did not buy but i am still planning to, thank you, yes i will watch it during my holidays which is coming up in less than a week, anyways also, thank you for your videos!

[@DarkWolf887]

would it be possible to use a function generator insteat of the internal clock? I am connecting a function generator (1000KHz, 3V, 1.5 Offset) to the positive pin of the comparator and in the negative I am using the VRefInt. However I just get a HIGH in the output of the comparator. :(

[@Weblearning1]

What do you want to achieve? Counting pulses? Something else?

[@DarkWolf887]

@@Weblearning1 yes. But I don’t know what is the best option for this. I’m afraid that connection a 3.3V, 1KHz signal is gonna be a too high frequency to get to trigger at the voltage reference (1.2V).

[@tomhyhlik1788]

thanks

[@gikusa2063]

hello, i try to make pwm in TIM2 as you made but it doesn't work, may i make somethings wrong?

[@Weblearning1]

There are different settings to play with till you get it to work correctly. I cant tell what you made wrong.

[@kameleln1617]

I am beginner in stm32, how you can log PA5 to LD2 and to swtich after that with Tim2_CH1, thank's in advance.

[@Weblearning1]

Sorry, didn't understand your question. Try to elaborate.

[@naasikhendricks1501]

Cool

[@aitrile7708]

thank you

[@Weblearning1]

You're welcome

[@srishtisingh1688]

The following code is showing errors in my PC please help and inform why an error is occurring.

[@Weblearning1]

What type or error?

[@Homo_neanderthal]

Go study units. You cannot compare sec and hz, they are different units