My Slim 2AA Battery Node

[Komaandy]

@gohan said in My Slim 2AA Battery Node:

LDO

@gohan
Hi, i added a WDT now into the MotionSensorSketch.
Well at least i guess i did. I just read about it , never used it before. Does the 1Mhz Optiboot boatloaders support this ?

Unfortunalty I didnt recieve my 3,3V boosters yet and i dont have LDO´s around.
Concerning the bootloaders. Do you have a suggestion which one to use ? As I read that sticking to 1Mhz is important when using only 2AA batteries because of instability when voltage goes belowe certian values.
Obviously i could use more batteries, but then i cant supply the nRF2401 from the board right ?

// Enable debug prints
#define MY_DEBUG

// Enable and select radio type attached
#define MY_RADIO_NRF24
//#define MY_RADIO_RFM69
#define MY_NODE_ID 40
#include <MySensors.h>
#include <avr/wdt.h>

unsigned long SLEEP_TIME = 120000; // Sleep time between reports (in milliseconds)
#define DIGITAL_INPUT_SENSOR 3   // The digital input you attached your motion sensor.  (Only 2 and 3 generates interrupt!)
#define CHILD_ID 1   // Id of the sensor child

// Initialize motion message
MyMessage msg(CHILD_ID, V_TRIPPED);

void setup()
{
	wdt_enable(WDTO_2S);
	pinMode(DIGITAL_INPUT_SENSOR, INPUT);      // sets the motion sensor digital pin as input
}

void presentation()
{
	// Send the sketch version information to the gateway and Controller
	sendSketchInfo("Motion Sensor", "AndyWasHere");

	// Register all sensors to gw (they will be created as child devices)
	present(CHILD_ID, S_MOTION);
}

void loop()
{
	// Read digital motion value
	bool tripped = digitalRead(DIGITAL_INPUT_SENSOR) == HIGH;

	Serial.println(tripped);
	send(msg.set(tripped?"1":"0"));  // Send tripped value to gw

	// Sleep until interrupt comes in on motion sensor. Send update every two minute.
	sleep(digitalPinToInterrupt(DIGITAL_INPUT_SENSOR), CHANGE, SLEEP_TIME);
 wdt_reset();

}```

[gohan]

Actually you would have to put wdt_enable(WDTO_8S); right after Loop() and wdt_disable(); before calling the sleep (this is what I copied from another sketch). The wdt_reset you cold use in the middle of the loop in case you have a function that could take long time to execute and it may trigger the WD timer so you can reset the timer (you can play with the length of the timer according to your needs)

[Komaandy]

@gohan
maybe like this ?

void loop()


{
	wdt_enable(WDTO_8S);
	// Read digital motion value
	bool tripped = digitalRead(DIGITAL_INPUT_SENSOR) == HIGH;

	Serial.println(tripped);
	send(msg.set(tripped?"1":"0"));  // Send tripped value to gw
wdt_disable();
	// Sleep until interrupt comes in on motion sensor. Send update every two minute.
	sleep(digitalPinToInterrupt(DIGITAL_INPUT_SENSOR), CHANGE, SLEEP_TIME);
 

}```

[gohan]

that's what I found. You could also use wdt_enable(WDTO_2S) I think. I haven't done any test yet on this.

[m26872]

@Komaandy Try to remove all your Serial.print.

[JonAndersen]

1. Has anyone used NRF24L01+ + PA + LNA on these modules ?

2. Any reason why it shouldnt work out of the box ( does AA batteries give enough power to drive them on LOW settings? )

3. What type of battery monitoring is recommended on these ones? The resistance or the library way?

I just got 90 PCBs, beautiful, fast shipping ( i think under 2 weeks to Norway ) and looks well made.
I'll drop one in each beehive I have ( 7 ) and see how long they last

[Komaandy]

So, it seems i made some progress.
After changing to the @GertSanders bootloader ( https://www.openhardware.io/view/33/Various-bootloader-files-based-on-Optiboot-62) all the PIR nodes seem to be stable.
I´m using these settings

Wish me luck :)

[m26872]

@Komaandy Yes, using 8MHz instead of 1MHz is perhaps a good idea. Stable enough at room temperature, well proven and will e.g. solve a "Serial.print()" interrupt loop issue. Just remember that you'll lose ~25uA if you'll leave BOD enabled.

[Nca78]

@m26872 said in My Slim 2AA Battery Node:

Just remember that you'll lose ~25uA if you'll leave BOD enabled.

No, on ATMega328 MySensors disables BOD before going to sleep.
So extra consumption from BOD will only exist when node is active and in that case it's negligible.

[m26872]

@Nca78 Ok. Thanks. Since ever, or only from 2.x ?

[Nca78]

@m26872 no idea I started MySensors with 2.x :P

[Komaandy]

Update : Day 3 and still all PIR nodes are working ;)
I´m using the given sketch here.

[Komaandy]

Still up and running stable.
8Mhz Bootloader did the trick for me :)

[m26872]

@Komaandy Nice! Thumbs up for 8MHz (and your "dark-style Fhem" - same as I use) :+1:

[Komaandy]

@m26872
thanks again for this great idea and that you developed these fine boards !
And by the way...
As you are using fhem as well...
How do you manage to reset the tripped "1" in Fhem ?
I just added a delay and a gw.send"0" to your sketch :), but using fhem would be more sophisticated actually ...
Thanks

[m26872]

@Komaandy said in My Slim 2AA Battery Node:

How do you manage to reset the tripped "1" in Fhem ?

I don't. I just use the last trip time as it's state and then notify (e.g. light or push message) on trip. I think it should be very simple to make a notify with a timer "at" to reset it after a while, if you wish.

[siod]

just want to mention that I am using successfully the same Bootloader @Komaandy is using for about 2 weeks now. So it seems like my problems with freezing nodes are depending on a bad or too slow bootloader...

[buxtronix]

All of the ducting near me is a bit too slim to fit sensors based on this, so I decided to design and print a case instead.

Does the trick nicely, and I also chose to use proper AA battery clips to retain a good connection, as the cable-tie battery assembly wasn't holding well for me!

On the Thingiverse page I have a link to the original OnShape doc.

https://www.thingiverse.com/thing:2418194

Thoughts, suggestions, etc will be much appreciated!

[Oliviakrk]

Hi

Did anyone make DHT 22 slim node with MySensors 2.0? I created one Node from modified MySenors 2 example...But I get a feeling that it is freezing sometimes (but then again comes back to life).

[mfalkvidd]

@Oliviakrk the dht22 needs at least 3.3V to function properly. See the datasheet.