This mode has half of fast pwm mode frequency.It is preferred in motors control(pictures from atmega datasheet). In this mode Timer 1 count from a BOTTOM value to a TOP(which can be max in top of the triangle signal or set by OCRnx) value after that it not overflow it countdown from TOP value to BOTTOM value and repeat(triangle wave). Next we will take Timer 1 and put it in the phase correct pwm mode. – OCR1A and OCR1B registers with bits for the duty cycle of the PWM signals for pin 9(OCR1A) and pin 10(OCR1B) – TCCR1B it has the bits needed to choose the prescaler and the other two bits neded to choose the mode of PWM – TCCR1A it has two of four bits needed to choose the mode of the PWM(fast pwm ,phase correct pwm etc) and the bits who manage the mode to set pins high or low Let’s talk about Timer 1 a little! As we mentioned in the previos post Timer 1 manage pins 9 and 10 and for that we must work with some specific registers like: This thing means that Timer 1 has a higher resolution or it can count longer. The main difference between Timer 1 and Timer 0 or Timer 2 is that it is a 16 bits timer(instead 8 bits the others) so Timer 1 can count up to 65355 insteat to 255. If you like the article click the follow button from social media to stay in touch with us! I was using the full 16 bits resolution which I found necessary to get a smooth fading effect due to the very non linear visuals from driving leds in this manner.Please let us in the comment zone any suggestions that you think will improve the article! I was a bit horrified when I looked at the reference manual, the length alone was daunting.Īlso on the Mega I was using timer direct PWM (Hardware PWM) to control LEDS also 3 channels per timer. Is there a library that could help do speed/accel control or would I need to dig down into the chip. Could I use the 4 PIT timers to do exactly the same thing in the Teensy? I might be able to use the TeensyStep but I think it does not have speed control on the fly which I was using in my project here that required a more natural movement rather than precise. With Mega for the steppers I was not using any libraries and controlling 3 motors with each timer using interrupt to fire the step and then adding whatever delay needed to the OCR inside the ISR (not really PWM of course), I am assuming this kind of scheme is what you call SoftPWM. It really looks like a complete other world here compared to where I have been with the development and ease of use just over the top really. Looking at the voice part it would seem to be a piece of cake. I guess what I am asking is what is the best way to proceed to configure to get my 4 stepper, 11 pwm's ? I really don't have a clue at this point. Is it just the chip that has these multitude of timers and they are not wired out on the board. I had thought I saw somewhere that there were many timers on one of these chips but now it seems it may be even more limited for PWM type channels than Mega. Well it came yesterday, maybe too quick really, now I am trying to figure out how to proceed without running down 100 rabbit holes. So I started looking around and had heard about Teensy, dug in a bit and ordered a 3.5. I had been working with Arduino Mega and was running into number of timer limitations with running that many channels of PWM and steppers and then definitely hit a wall when I needed more than one voice channel, the poor little 8 bit guy just couldn't do it. I am working on a project that requires 4 stepper motors, 11 LED pwm dimmers, and 2 or 3 voice channels.
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