ATinny85 Sleep Flowcode

[Matrixv8]

Hi everyone, I have been trying to write a code to put ATtiny85 to sleep but with no success. I would really appreciate an example in Flowcode 10. I am using USBtiny as a programmer.

Thank you.

[mnfisher]

It is possible to do:

In supplementary code:

Code: Select all

#include <avr/sleep.h>

Then in a code block:

Code: Select all

set_sleep_mode(SLEEP_MODE_PWR_DOWN); // Other modes are available - see sleep.h
sleep_enable();
sleep_cpu();
sleep_disable();

You'll also need something to wake up the MCU - for example a pin change interrupt (or wdt interrupt etc)

Martin

[Matrixv8]

Thank you for your help.

[Matrixv8]

Martin it worked perfectly, the supplementary code was key. Now, I have tried everything to wakeup the ATtiny with INT0 pin7, port B2 with no success. Any idea?

PS: I will keep my questions to a minimum.

Regards,

Pierre

[mnfisher]

Hi Pierre,

Can you post your code.

I'm not at a computer at the moment but something like:

Code: Select all

Enable interrupt 
Loop
  Sleep
  Do something 
End loop

The interrupt macro needs to be short - it doesn't need to do anything (it could be an empty macro) or it could increment a 'wake' counter.

If you are using a rising edge interrupt — the pin needs to be pulled to ground (with a resistor either internal pull-down or external) and if you are using a button watch out for bounce (which might give multiple wakes per press)
Falling edge interrupt needs internal pull up or resistor to VCC

Martin

[Matrixv8]

Hi Martin, thank you for your help. Attached is my Flowcode. I use a 10K pull up resistor on port B2. I use a digital high low output, so no switch noise. I send a high to low pulse. The INT micro works until the chip goes to sleep then I can not wake the chip unless I reset it.

Thank you for you help.

Pierre

[mnfisher]

The 'sleep' is outside of your loop, so it when the MCU 'wakes' it will be just 'fall off the end of the program' - this actually just has a while(1) ; loop - NOT a reset. So move the sleep into the loop and it should work as expected (or add a 'reset' after it?)

I also forgot to mention - if using a separate device for waking then ground must be common.

Martin

[Matrixv8]

Hi Martin, moving the C code in the loop was the first fix to my problem, It would go to sleep but not wake up. I found that the INT0 on Attiny85 with Flowcode 10 was not waking up the micro. I had to use the IOC PortB2 and click on the Port B2 pin 7 of the chip icon inside the Inerrupt command icon for it to work. So both fix created a solution. I am attaching an example for the readers hopping that it will help them as I spent a long time to figure it out.

Again a great thanks for your quick help.

Pierre

[mnfisher]

Thanks - glad you got it working...

Martin