MySensors on ATTINY85

[axillent]

@Joseph-Macaulay the version of RF24 is comming with latest MySensor contains a software SPI driver able to work on tiny MCU

[vtento]

• @Joseph-Macaulay Hi, this is the sketch that I use for Themp sensor

MySensors85.ino

[mrendu43]

hello
I dont understand why didnt you use reset, and delcare it as input pin?
as i know it can be declared as io

[Sweebee]

Oitzu and I (testing :P) are currently working on the Attiny support. To test you can download this library (the same as the original one except that it includes the attiny).

Its working so far.

Bugs:
Your node id is the same as child id (if you set a different child id, somehow the attiny ignores it and makes it the same as your node id).
Sleep is working with interrupt but it does the setup again after wake.
Sleep / timer is not yet working.

library: https://github.com/Oitzu/Arduino/tree/master/libraries/MySensors (You can replace it with your existing mysensors library)
example sketch thats working: http://pastebin.com/xRu2JNQ9

wiring:

                  +-\/-+
                 1|o   |8  VCC/CE  RED/ORANGE
 YELLOW  CSN     2|    |7  SCK     GREEN
 -       SENSOR  3|    |6  MOSI    BLUE
BLACK    GND     4|    |5  MISO    VIOLET
                  +----+

[Andy]

Awsome work Oitzu and Sweebee!

Just tried it out and it works perfect :)

Have you succeeded with getting the sleep/timer working? I've tried but discovered that my skills aren't good enough.

[Sweebee]

Not yet. Maybe next week. To much work at school right now ^^. But when it works i'll post it here.

[Andy]

@Sweebee Got it working last night (I hope!), I haven't measured the power consumption yet.

It doesn't have the resolution of ms. To save battery the attiny85 will sleep for 8 seconds, then wake up and go to sleep again. So if you call gw.deep_sleep(7), it will sleep fox 7x8=56 seconds. It is possible to get a more precise timer by calculating the best combination of sleep timers. For example if you want to sleep a minute, sleep 7x8s=56s and then an additional 1x4s=4, total 60s.

It needs some cleaning up and correct naming/commenting/testing e.t.c.

void MySensor::deep_sleep(int time) {
	// Sleep alternatives:
	// 0=16ms, 1=32ms,2=64ms,3=128ms,4=250ms,5=500ms, 6=1 sec,7=2 sec, 8=4 sec, 9= 8sec
	int ii = 9;	// sleep 8 seconds at a time.
	byte bb;
	int ww;
	if (ii > 9 ) ii=9;
	bb=ii & 7;
	if (ii > 7) bb|= (1<<5);
	bb|= (1<<WDCE);
	ww=bb;

	MCUSR &= ~(1<<WDRF);
	// start timed sequence
	WDTCR |= (1<<WDCE) | (1<<WDE);
	// set new watchdog timeout value
	WDTCR = bb;
	WDTCR |= _BV(WDIE);
  
	// Count some sheeps.
	for(int i=0;i<time;i++) {
		RF24::powerDown();	
		cbi(ADCSRA,ADEN);                    // switch Analog to Digitalconverter OFF
		set_sleep_mode(SLEEP_MODE_PWR_DOWN); // sleep mode is set here
		sleep_enable();
		sleep_mode();                        // System actually sleeps here
		sleep_disable();                     // System continues execution here when watchdog timed out   
		sbi(ADCSRA,ADEN);                    // switch Analog to Digitalconverter ON
	}
}

[n3ro]

has someone tested digispark? That would be to test a lot easier.

http://digistump.com/products/1

[mntlvr]

@Andy said:

Awsome work Oitzu and Sweebee!

Just tried it out and it works perfect :)

Have you succeeded with getting the sleep/timer working? I've tried but discovered that my skills aren't good enough.

Hi Fella,
I just came across this post several weeks ago , I was looking for a smaller cheaper way of making a binary switch to use with my Veras. After reading the "Great debates" whether an ATTiny 85 could be used for such a purpose, I decide to try what was here and by the individuals who said they had made them work. I built one and powered it with a Li-Ion 3.7 v 4000 Mah battery. I have had it in use now for about a week and so far it works great. I have not been able to make the WDT work but from my test so far , running the ATTiny and nRF24l01+ from a Li-ION 4000 Mah battery , it should last for months. Now the the entire circuit is drawing 6.0 ma and when tripped the unit drew 7.5 ma. Now I am sure the current was higher than 7.5 ma when in transmit but it would be for just a very small amount of time. Thanks for the leg work you guys did to make this project for me happen.

[ted]

@Sweebee
Do you mind sharing your library again? The link is no longer working.

[Oitzu]

@ted you are probably searching for this: https://github.com/Oitzu/mysensors-Arduino-attiny/tree/master/libraries/MySensors

But i need to seriously warn you, it is horribly outdated. The repository do not got the love it needed. ^^

[ted]

@Oitzu

Thanks!!