The WORKBENCH part 1


tnx kees
actualy I’m working on the PIR at the moment :sunglasses:


I had ordered some new PIR’s with a very short (1.8 sec) delaytime.
That’s the time the output stays 'one after movement detection.
The signal wakes up the 32U4 (leonardo) processor and trigger an LoRaWAN alarm signal.
This very low current type has no adjustable time but you can order them between 1.8 sec and 1 hour delaytime.
Nice, now the processor can go to sleep faster, in the code I can set a counter or timer to prevent sending constant alarmsignals when a burglar is walking in the room.
And, if necessary I can count people :wink:

bottom view :scream:

(Gry Kyo) #224

Just curious (and probably too lazy to scan posts, sorry!) but including or excluding the 20uA of the PIR, what sort of quiescent current do you see with the 32U4 based node (sleeping)? Similar project scheduled for my workbench but likely design to be sealed for life for harsh in the wild deployment so ultimate node life == battery life. Still not sure which MCU I will start with.



the 32U4 is not the most energy efficient processor … and this usb node ‘thing’ has also a rn2483A / ams117 3v3 / dual level shifter so this is not designed for extreme low power (usb stick)
just for fun , it should run TTN UNO code to.

Just have a look at this CMWX1ZZABZ processor.
And the arduino IDE is coming soon

(Gry Kyo) #226

Thanks again @BoRRoZ! That looks like a very interesting module.
We are heading towards proprietary and cheap super low power solutions now. Bumps the regulatory/CE questions from that other thread up the priorities a bit… adds to the end of a very long list!


I forgot to mention this one, uses the same processor.

The Arduino MKR WAN 1300


I went to the shopping mall to buy some glue… and came back with a pir home alarmsystem with 2 remote controls for 8 euro :yum:


is there room for an arduino+rn2483 ??? … lets take it apart




there’s not alot of room inside, but he the thing works for the price of an empty enclosure.
interesting is that it uses the same chip BS00001 as all the other china PIR’s
If you take out the electronics there is room for your own pir loralarm … thing is not waterproof
maybe a TINY LoRa inside so you can still make use of the remotes leaving the original pcb ?

The BARGAIN basement part 5

Lol, what’s inside? I wonder… Didn’t we al start “fixing” tv’s or radios like that?



3v3 ‘power’ unit with LIR 2450 - its also very easy to make your own charger for this type of LI-ION battery.
when charged connect it to this dc/dc converter which gives you a constant 3v3 output for your mini node :sunglasses:


when I remember correctly, that one has no undervoltage protection …


true … now I think about it, there’s a problem because I wanted to read the operating voltage internally but that’s stupid , its always 3v3 :rofl: because of the dc/dc board.

my idea was to free a pin, like mentioned in the 85 topic, and use that for a PIR so I can switch the use case : PIR or TEMP

have to think a bit now because you may drain these coin cells to ca 3v, drain more and you damage them.
so we have no pins left …how to detect ?



and why not using the attiny167 board?
some more pins but not much larger?
removing the 3V3 regulator and the pwr led it shout not draw much current.


yes sure… I can build it with any processor or RF module, but I was inspired by the ATtiny85 topic and I looked and found everything in my workplace that I thought I need to ’ quickly ’ build a small node… :wink:

btw the board you mentioned needs a levelshifter with the rfm95

this one has a 2.75V cutoff but maybe you can tweak that a bit by changing a resistor

  • update small lithium protection boards arrived… have to test the cut off voltage first



I had this one in mind


yes that’s the same idea, but be carefull, these little protection boards are specific designed for 18650 batteries and they have different characteristics then that LIR2450

I tested a few in the past … if they say 'cutoff voltage = 2.75v ’ don’t believe them … test it first and don’t be amazed when the protection kicks in @ 2.35v ’ :sunglasses: … or never




finally … The REAL DEAL ! thank you

(Remko) #238

Good to see that stuff finally starts arriving. Enjoy it :tada:



Leonardo Pro Micro ATmega32U4 8MHz 3.3V !

so direct connection to RFM95 / RN2483 possible ? a mini TTN node ?


always run BLINK to check module :rofl:



  • identifying individual components (click for BIG)

TTN UNO - BETA release - Documentation
HowTo: Update RN2483 Firmware on 'The Things Node'

after loading the passthrough sketch in the TTN node


I started this ESPlorer V2… nice free tool for the ESP8266 and now extended with preprogarammed buttons for the RN2483


to start just double click ESPlorer.jar


tool seems to work




testing TTN node with RN2483 firmware 1.0.1
loaded with the basic sketch
Rx = 3.8 mA
Tx = 14.5 mA

first conclusion … don’t leave the basic sketch in the node with the batteries :sunglasses:

I will have a closer look at the ‘sleeping’ code … and ask @Charles and @rocketscream , the low power specialists, for advice how (and if possible) to improve this TTN device

now I will upgrade the RN2483 firmware and test again :

update 1

update 2

ok firmware updated to 1.0.3 with the passtrough sketch and the semtech tool

  • that was a bit disappointing… with the same basic sketch but with the updated firmware no difference, continue