Arduino Forum

Using Arduino => Microcontrollers => Topic started by: wornoutflipflops on Mar 20, 2017, 03:25 am

Title: Servo8Bit not working on ATtiny45
Post by: wornoutflipflops on Mar 20, 2017, 03:25 am
I'm using the tiny45 for a project where I have to read two ADC's and control an LED and a servo. I'm using the Servo8Bit library and configured the ATtiny at 8MHz internal.

The first ADC value controls the LED brightness and the second ADC value is compared with a threshold to decide whether to actuate the servo (angle is predetermined).

When I tested this on the Arduino MEGA board using the standard Servo.h library, everything worked fine.
Even on the ATtiny, the ADC's and PWM's work perfectly when I read the analog inputs and output the same voltage on the PWM pins. But everything stops working when i #include the "Servo8Bit.h". Even the LED stops glowing and servo is dead.
Just using the preprocessor directive renders the tiny45 dead. And comes back alive when I remove it.

So I guess I've missed something in the procedure, or there's a problem in the library.
edit: Library source - http://www.cunningturtle.com/servo8bit-library-version-0-6-released/ (http://www.cunningturtle.com/servo8bit-library-version-0-6-released/)
Title: Re: Servo8Bit not working on ATtiny45
Post by: DrAzzy on Mar 20, 2017, 04:18 am
Is that library specifically meant for the tiny x5 series? The timers available on the x5 are significantly different from those available on other attiny boards.

Also - whenever you use any servo library, it's going to take out some of the PWM outputs (1 or 2 on the x5 series, depending on whether it uses timer0 (which will also take out millis() ) or timer1 (which is totally unlike timer1 on any other AVR micro other than the tiny x61 series)
Title: Re: Servo8Bit not working on ATtiny45
Post by: wornoutflipflops on Mar 20, 2017, 07:28 am
Thanks for the reply..
I am not using the PWM's simultaneously so had ruled that out. I detach the Servo as soon as it's scope is out, on every iteration of void loop.
So I think it's the compatibility issue as you've said. Can you suggest a good servo library for the 45? With the detach function operational?
Title: Re: Servo8Bit not working on ATtiny45
Post by: wornoutflipflops on Mar 21, 2017, 02:02 am
I was going through the forum for similar topics and found a couple of libraries for the tiny45, so I downloaded them and tested. One of them, Servo8Bit2 seems to work. No problems till now.


Thanks for the help.