Hi.

This is a project in progress. So I post here if I need to ask for some help (and I think this will be the case).

First, thx to @tbowmo for his work on 32bit GW
And thx to Sparkfun, Adafruit etc.. for all their work

I would like to introduce to you : M.and Ms Sam&LoraLip and their baby child
A board with a 32bit Atmel Atsamd21e17 (128k, e18 is 256k) and Lora (Long range RFM95W, but there is also a nrf24 smd footprint), with Lipo Charger. And two proto childboard.

Left top : M.&Ms Lip the mainboard
Right top : W(H)eather childboard, nice sensors for meteo
Left bottom : Adafruit Feather M0 ???
Right bottom : Chi-Mote, (humm missing inspiration..) a childboard I have made for the Feather. For gesture and 3d control with rgb feedback. Sort of wiimote but smaller with gesture..my Chi in this one

Specs a little bit below;

So As you can see I have been inspired by Adafruit Feather M0. No advertisement here It was out of stock so I assembled one. First, to be sure to have a 32bit board (atsam based) which works. And finally, because I wanted to have a simple lipo capable board. But that was not enough..more things.

Briefly :

• I keep lipo + usb from Adafruit (as it's a charger, so it's nice to have usb on this one). Usb can be used to upload sketch as native usb.
• here it's 32pins TQFP ATSAMD21E16/17/18, I bought an E17 128k (on Adafruit, it's a nice big 44pins VQFN G18 family, first time for me, thx to my reflow). E17/18 cheaper compared to G18. If I would like to use L picopower family, I just need to swap 2-3pins.

And I added:

• footprint for usb filtering on +5v and shield
• footprint for fuse
• atsha204a
• eeprom in case
• rgb led
• footprint for Nrf24 smd, RFM95W (not received yet), RFM69HCW (pincompatible with RFM95W if I'm right)
• for RFM95W, wire style antenna or connector
• MYSX connector (maybe I will reduce it)

I have made two child boards

• Weather optional (or not!) sensors : opt3001 for light, veml6070 for UV, SI7021 temperature/humidity, BME 280 temperature/humidity/pressure (in case I use this one I don't need si7021 of course), there is also AS3935 for Lightning detection. + switchable battery voltage sensor
• For the mote : RGB led, APDS9960 for proximity&gesture, 6DOF LSM6DS3 (6DOF is enough for what I want to do but maybe a better/expensive MEMS could be fun...)

Ok you really are cool guys if you are still reading. Now the pics:

Nrf radio style

Long range RFM95 style

Weather child board on mainboard

Assembled (no radio soldered, still doing basic tests), weather not assembled

Chi-Mote for MYSX connector (I will add an IR led as I have enough space, more fun)

And Chi-Mote for Feather, on top of it no radio soldered yet.

With a small lipo and humm..wireless charging, more Chi

And a very short video of my kungfu gizmo Gesture part is buggy for the moment so not activated and on the 6dof I only use single/double tap. Connected on a nano. but fixed on the wall, or few mobile in the house, very cool.
https://youtu.be/w8yZao3IWJo

Current status:

• the feather I assembled works ok. bootloader ok, and blinkled in arduino ide ok
• weather not tested yet, Chi-mote, all is good except gesture (I suspect power+infinite loop in lib!). Add an ir led
• my mainboard: sam-ba bootloader for ATSAMD21E17 well sent with jtag in Atmel studio, but I get a no device connected on comport in arduino. I am investigating if it comes from boards.txt ..
  Few things to improve on mapping part

Certainly more things to say..but that's ok for today! I'm enough happy.
Thx for you interest and feedback.
See you soon

Meet Janus project, a premium USB dongle by Tekka and me

Dual RF gateway with external antennas.

• nrf52840 with 20dB PA + SMA connector. So it can be compatible with MySensors, and/or zigbee..
• rfm69hcw/rfm95 long range + SMA connector . module has all DIO pins routed for sw driver optimizations.
• reset button
• user button
• RGB led
• high PSRR RF/analog 700mA LDO
• usb protected
• 4layers board
• enclosure size : 52x21 (thickness 11mm). compact!

Enclosure is just a quick proto, I'll improve quality, or I would like to try online multijet service, I'm curious

It's very recommended, for better performance, to have some distance between antennas.
So, for example, I'll use a shorter antenna (without cable) for 2.4ghz, and a "remote" antenna (with a cable) for 433/868/905Mhz, so it can be used with different kind of antennas.

We choosed external antennas, because

• versatile use
• better range especially when dongle is close to lot of stuff which could affect range in case of a pcb antennas

Hey

I am enthousiast to show you my very new project : my low power multisensor for light loads.
My roadtrip in the lowpower jungle world.

I wanted to make an update on my other "mytinycamel" post, but I would like to explain my way for this board, so...Ah, and I will make it openhardware of course

Why this board as I have already Mytinycamel in the pipeline ???

I want to factorize some of my needs and costs (and that is not a question of me only, I have family, friends..which want my boards too, so why not make it the best I can). I need to have in each room, at least or optionnally, one :

1) We are here for Sensors :

• PIR motion sensor : LHI968 + e931.96 ic (integrated LDO and autocalibration for common PIR sensors)
• temperature/humidity sensor : SI7021
• ambient light sensor : OPT3001
• Accelerometer (why not for antithief) : LIS3DH
• a reed switch for the door
• a buzzer (why not, for fun, optional)
• indication led : for the moment, ws2812b

As you can see, I have choosen all these sensors for their cost/ultra low powermode. You can find better IMU but >6€ (it is for antithief, so I don't need a 9DOF!)
WS2812b, buzzer are on an enable/disable power rail, so in sleepmode I will disconnect it. Ambiant light OPT3001 is interesting too. You can set by i2c, light thresholds and trigger an interrupt on your mcu which is in deepsleep. Could be useful in some scenario.

my first problem is about PIR motion sensor ic, it needs 2.6V min. And Mytinycamel concept is based on a 2Vto3V variable vcc.

Humm..That is why I have designed this board. I want something the most low power I can, and 3V constant (2.7V min). Go to switching regulators, not powering it off like with mytinycamel.

2) DC step-up switching regulator : TPS610981(x)

This one rocks, it's a "pépite". French revealed (maybe my bad english too lol), I say this when I like it and compare this to a gold nugget I have digged digged in the river of the lowpower, yeah:) lol I hope your are laughing of my bullsh**, because I can't stop!

Unfortunately, this ic is not handsolderable. I will use reflow process. But I am already making a rev1.1 with a crazy SOT23 buck more friendly, but a buck is not one 1.5V cell, it would need 4x to get same result

Common switching reg (stepup or buck) are not very efficient at lights loads (like 10uA, during sleepmodes..). And they use few or more uA in quiescent current Iq. All uA added, will be increased due to efficiency.
My choice is : for controlled light loads, I go to stepup, and for bigger loads a buck.

Shortly, its specs :

• 0.7V min voltage, so you can get every drop of one 1.5V AA/AAA
• Ultra low Iq, 400nA
• 80% efficient even at 10-15uA!
• two power rails (in datasheet lot of interesting variant).
• now crazy thing, first you have bypass mode (if vin>3V for the 3V variant, vin is directly connected to vout), and then 0.7-3V vin -> 3V vout. Now if you want to disable the stepup, it goes in low powermode, which means the power rail n°2 is disconnected, but power rail n°1 still remains at 3V in ultra low Iq of 400nA, 80% efficient! So it's possible to cut off things with vout2, and have low power light load things on vout1.

that's like pizza, I want the complete. ahah, really cool, isn'it ?

now, its cons are it is not friendly to solder, and it is 2x50mA max. But we must do things smart..

3) A little word about batteries, energy harvesting..
I have thought a lot about this, read lot of interesting design notes. I think it's a lot a matter of taste but :

• 3V coincell. Interesting, but not enough if I want to use RFM69 (Tx mode is a eater). It could be interesting used in a solar harvesting extender mode. But it would increase my cost, and I think I can last very long time how I will do, and for the use I need; and for the cost... And solar require some placement, which is not really the best usecase for this node.
  But it is thin, so I don't forget it, it can be cool too.
• 1.5V AAA not bad, thin, 1200mAh. definitely not bad compared to coincell. I like it
• 1.5V AA 2500mAh alkaline, 3000mAh. That IS Cool !! You have always an AA or AAA somewhere and here we go!
• 1.5V LR14 : 8000mAh. Wow! If I have place, like at ceiling edge, sure I will use it.
• lipo. definitely not interesting for this node. Too bad selfdischarge rate. can vent.
• Same thing about phone battery. not available everywhere, how long time for a model, can vent too, and self discharge is not the best. maybe 2years with no load. I don't imagine with a load..Compared to primary lithium which is 10years min theoretically...
• rechargeable lisocl2. interesting too, but not available everywhere. Expensive, need a buck, ...

As you can see, I am searching for less maintenance (less battery replacement...), cost and availability. So ok a booster is less efficient than a buck, but with a buck you can't use only one AA/AAA, héhé! A booster is not as efficient as battery powered only, but you can have constant vcc, and use the whole battery.

So it's my analysis, my personal interpretation from gurus of low power...maybe there are better option..Don't hesitate to tell me. I do not argue to be an expert

My favorite config will be :

• 1AA lithium 3000mAh
• when I can, 1LR14 8000mAh
• for ultra thin and I accept worse maintenance: coincell
• try the rfm69 listenmode. one other thing why I wanted something efficient at light loads.

I suggest you to look at oregon battery lifetime calculator on google. and you will understand with one AA of 3000mA, if I have an Iq of says 30uA at 0.7 vin (a circuit Iq of says 15uA at 3V will give us 26-30uA at 0.7v vin batt end of life so the worse case). Lifetime of the system 3years mini with only one AA

4) Other requirements :

• rfm69 or nrf24 smd for the radio

• MYSX 1.5 Connector. That was really not easy at all to fit it!!! Lot of time, I was near to give up! But, even if I don't need it, it could be very helpful for debug. So I follow you on this @Anticimex

• LDO SOT footprint in case I don't want to use the stepup reg.

• ATSHA204A ic footprint : authentication (for PIR, reed switch...)

• Eeprom for OTA. Same thing, eeprom needs to be in low power mode.

• optional pullup for reedswitch...

• battery measurement

• smd jumper to choose if I want SPI bus Vcc on vout1 or vout2

• smd jumper to choose if I want I2C sensors on vout1 or vout2

• all component on top to boost production, or decrease cost if externally produced (we can dream!). I was not able! there was not enough space, so there is only eeprom on bottom. not bad!

• Make the best I can for improve overall quality and reliability like
  shielded ferrite for booster
  ferrite and emi bead for booster Vout, and another one between gnd_Booster/GND
  Optional capacitor near battery
  optional capacitor near ferrite to improve emi filter
  vias on board edge and near antenna pad to improve ground
  no ground plane on one edge of the board for antenna

PCB : Size 65mmx32mm
Height of the box depends on coincell, or AA. For AA it's 22mm, compact.

Last notes : I put this here in case you have feedbacks, or there are some infos that could help you...but It is not a noob board, sorry. Much more for reflow oven owner. How could we do to make things like this available for others??? I am thinking maybe of a simple eval board for the booster. Don't know if chinese would be interested in?
I have not ordered yet, I am making the last decisions, but my drc are ok. cool. just a matter of time, and chinese new year now...

Hi,

today I've almost finished a speaker build (it'll be a gift for family)

First, I would like to thx Paul Carmody who created the original design of these speakers : Overnight Sensation
https://sites.google.com/site/undefinition/diy-overnightsensations

I have just changed size and format (of course I kept the internal air volume which is very important)

1. I designed&printed a simple circle jig for my router.
   
   

2. So speaker drivers can be flush on front plate
   

3. Assembled the box
   

4. Crossover, port tube, foam
   
   with a special place to fit some electronics like

• rpi (for Volumio/LMS client, or a voice assistant)
• cheap dac & 2x50w amp from aliexpress

1. Now vinyling. I need to change these ugly black screws too.
   

Of course, I'm too excited (and not very patient ), so I've tested how they sound... Loud! Crystal sound with very nice boomboom

Not finished, but in good way

I know I don't give news about this project.
So, maybe I should show you few pics, just in case.. ,)

First, I prefer to say, we can't share code for the moment..not very release-able.

We are using completely custom code for this project. GW code is quite big, mysensors is an experimental version (sort of "v3"). Plus for all the features, sometimes it can need some tweaks in esp32 libs etc. for the moment, sw is still tied to this project&hw.

That said we have lot of neat stuff working, hw choices changed a bit too.

Here we go:

• asynchronous
• http webserver + websocket server
• mqtt client
• transport bridging
• embedded webapp for UI
• etc.
  Well I cannot make a list for the moment, there are lot of features.

Concept is autonomous simple network without need of a advanced controller, or when linkto/controller is down, that you can control and debug from your phone or computer. With step by step configuration, inclusion etc for easy getting started.

Pics of the app ?? Teasing ON!

The app is realtime and very reactive. Responsive and mobile friendly. This is a single page app. written with Vue, no jquery. lightweight Bulma CSS

I started to make some widgets.. there are also multiple filters for dashboard.

It will also be possible to get infos about network, rssi, stats etc

Lot of settings, I let you imagine them.. there are a few dedicated steps by steps too, handy for starters (like my family, friends..).

It's also possible to see all logs, downloading them, updating app files etc.

Teasing OFF, I prefer to keep some other nice features to show you later

don't ask for a release date plz, we're busy on lot of projects, but we'll try to do our best! stay tuned

Hi.

Here is an howto about OTA in Mysensors I made for jeedom french users when Mysensors 1.5 was released. So I translated it if it can be useful to you. Things should not have changed a lot I think. I have no time for the moment to check everything. So if you note differences, tell me here and I will update. I will update pics with latest revision of the software.

OTA, or Over The Air, lets you upload your sketch without ftdi, it's done wirelessly. Can be useful if your nodes are not accessible or you need to make signing changes for instance. To get this nice feature, you need to burn a dedicated bootloader.

In Mysensors, we can use two kind of OTA:

• 1st option : MYSBootloader, created by Tekka from Mysensors Team.
• 2nd option : Dualoptiboot or if you prefer Sensebender Bootloader (in Mysensors boards). But in this tutorial I will name it "Dualoptiboot". It comes from Lowpowerlab.

Difference between these two methods (updated from Tekka post http://forum.mysensors.org/topic/3453/mysbootloader-1-3-pre-release-myscontroller-1-0-0beta/9)

• MYSBootloader does not require external flash: OTA FW updates are transmitted offline, i.e. MYSBootloader communicates with the controller and receives new FW which is directly written to MCU, once FW is transmitted and CRC verified, MYSBootloader hands over to the new sketch/FW.
  Pro: recovery OTA possible, also with a faulty/buggy sketch (if sketch freezes, watchdog resets and MYSBootloader takes over), no external flash required
  Cons: Radio specific, i.e. different bootloader for RF24 and RFM69 radio (rfm69 work in progess) necessary, offline (no sensor data processing possible during ota).
• Dualoptiboot requires external flash: OTA FW updates are transmitted online, i.e. while the node is active. Once all FW packets are transmitted and CRC verified, the node reboots, dualoptiboot copies FW from external flash to MCU and hands over to the new sketch/FW.
  That means too that you need to ftdi upload your node sketch the first time or ota won't work yet as it is handled in the sketch.
  Pro: Radio agnostic (no radio specific code in bootloader so can be used in different scheme/protocols..), online (while node processes sensor data)
  Cons: Faulty FW (e.g. freezing sketch due to bad coding) cannot be recovered OTA => recovery via serial port necessary, external flash required

This tutorial is only for Dualoptiboot Bootloader, because I have not seen an howto for this option here yet. But some parts/pictures of this howto can be used for MYSBootloader upload.
If you want to use MYSBootloader, howto is here: http://forum.mysensors.org/topic/3453/mysbootloader-1-3-pre-release-myscontroller-1-0-0beta/9

By default, Dualoptiboot bootloader is 8Mhz Internal + 1.8V BOD.

What do you need:

• SPI eeprom, jedec compliant, like AT25DF512C-SSHN-B. For other eeprom and compatibility, you can check this post https://forum.mysensors.org/topic/3160/ota-flash-types-for-mysensors
• for evaluation or some diy projects, I did this evalboard https://oshpark.com/shared_projects/m5Uugjx5 or you can find it on opensourcehardware. No need of course if you have a sensebender, moteino etc as eeprom is already there.
• I use an USBASP to burn the bootloader
• I use AVRDUDESS : http://blog.zakkemble.co.uk/avrdudess-a-gui-for-avrdude/ for fuse
• arduino 1.6.x
• Mysensors 1.5.x : http://www.mysensors.org/download/
• MYSController : http://www.mysensors.org/controller/myscontroller
• So in Arduino Ide, now you shoud see Sensebender Micro board in Boards\tools

Burn Dualoptiboot in your node

To keep things simple, or maybe not for others..imho it's so easy with a cheap usbasp (just few wire) than arduino as isp.

What looks my usbasp (clone, USBASP 2.0 LC Technology) and connections to your arduino or node.

Wiring on nano/micro/328p:

MOSI : D11
VTG : VCC 3.3V
GND : GND
RES : RESET
SCK : D13
MISO : D12

Once it's wired, burn fuses with avrdudess. Here the conf:

Note : even if my usbasp is a clone, I choose genuine usbasp in the listbox.

Just click on Write in "Fuses&Lock bits" section. Then read it to check fuses are well burned.

Now don't disconnect your usbasp.

• Go to arduino ide, choose SensebenderMicro, Processeur Atmel328 8Mhz, serial COM port, and USBASP programmer.
• Click Tools\Burn bootloader. You will get few SCK warning but that's not a problem, it's because I have an usbasp clone.
  Note: you could use avrdudess to burn the bootloader too.

Yeah, our OTA bootloader is burnt

In sketch

To enable OTA in your sketch, you need to add

#define MY_OTA_FIRMWARE_FEATURE 

or uncomment it in Myconfig.h

OTA management is completely transparent. Everything is well handled in process() and wait() methods (when you do a gw.wait or mynode.wait for instance...)

Important note :

• Don't forget a sleeping node can't receive an OTA. You can wait after wakeup for instance to see if you have somethings coming or I have not tried it yet but it seems now in mysensors libs there is smartsleep() wich manage the wait() after wake up.
• when you upload the new sketch, it is done during runtime, so you have to handle/optimize this in sketch. The best is if you detect an OTA msg, to pause process or sensors readings during the process or it will affect the speed of the OTA. I mean for instance if you read sensors, sometimes there are some delays in libs, all these things will delay ota or timeout it during main loop. Plus, if these optimization are not done and you run on battery, the longer time in TX/RX radio for the update, the more battery energy wasted. OTA can be fast 15-30sec if nothing slow it, or x minutes if not optimized
  So it's up to you to manage this, use non blocking/asynchronous code. The rest of the process is again completely transparent. Great!

How to upload a new sketch just with OTA

For this I use MYSController. It's not an .ino file that you will upload but the .hex one. So to easily get this file:

• In Arduino ide, go to File\Preferences, on bottom click on preferences.txt. It opens preferences.txt.

• Keep this file opened and close arduino ide (otherwise your changes will be erased).
• In preferences.txt, at the end, add this

build.path=C:\Arduino-Output\

or another preferred path. It will be there you will find your .hex compiled sketch files.

• Open arduino ide and compile/check your node project. You should now see your compiled files in the path you have set.
• Copy the .hex to Firmware path of MYSController

Launch your OTA update

• Launch MYSController and in Config/Serial, check the right serial com port.
• Click on "Refresh FW repo" so you can use your new .hex file.
  Note : When I tested this it didn't work for me so I needed to do this
  In Firmware folder, edit firmware_config.csv and manually add your .hex. Here an example where I added a Humidity .hex file for tests.

Type,Name,Version,File,Comments
10,Blink,1,Blink.hex,blinking example
20,TimeReporter,1,TimeReporter.hex,TimeReporter
100,Sensebender Micro,1,SensebenderMicro.cpp.hex,Sensebender Micro
110,Sensebender Blink,1,SensebenderBlink.cpp.hex,Sensebender Blink
120,Sensebender HumidityTest,1,HumiditySensor.cpp.hex,HumidityTest

• Now to wirelessly send your new sketch to your node, simply right click on the node you want to update. For sleeping battery node, choose "Battery powered Sleeping". So when your node will wake up, MYSController will resend the update. Awesome!
• click on Assign FW,
• choose the sketch

and voilà! OTA should start, and then your node will reboot.

I hope to have not missed something important. Please tell me, and I will add in this post.
This howto was made some months ago, so I'm note sure if it's exactly still the same, but that should be almost ok. Try and test and tell me. I hope it will help at least, as it is something often asked..If all is ok, don't hesitate to put it on a better place (I'm not sure if it's the best place here)

Enjoy!

Hi

I will show you here a board I have roughly drafted last night (one night=one board lol ). I was bugging on something and wanted to distract my brain with an other thing..and it was too long time that doing this board was tempting me!

Briefly the context:

• I have already done a multisensor with PIR on one cell with booster:http://forum.mysensors.org/topic/2951/my-mysx-multisensors-board
  Not released, because I need to fix few things in my files (like maybe remove the ws2812b led which doesn't work well for me at 3v, 8Mhz. Works ok at 16mhz..and few others things). The PIR controller, here is too much exotic, to be a durable sourcable solution. I have enough of these PIR ic for me but not enough for family, friends...
  The new board, presented here, will follow my custom box.
• I have already made an eval board for PIR which needed some tuning, based on discrete components, no exotic chip: http://forum.mysensors.org/topic/2387/low-power-pir-breakout-board-for-mysensors-and-evaluation
  Based on ST AN4368 app note.
• and some time ago, I felt in love with this design note from TI, http://www.ti.com/lit/ug/tiduau1a/tiduau1a.pdf
  This design note is a POC for a 10years PIR on coin cell! I felt so in love that I have almost designed an eval board for this crazy CC1310 mcu that I absolutely want to try since so long time (yep, there is RF, but like some people says, read books and follow the 5 master rules, btw I have a spectrum analyzer, not a network one unfortunately! will see what I get. I know I'm maybe too much geeky
  So, this design appnotes uses the CC1310 which is a very well optimized mcu with optimized power domains for sensors and RF. With a well written software, they get this excellent result of theoretical 10years.

So, what if we applie these two appnotes to our favorite 328p mcu?? And my board was born My first coincell multisensors board (never say never!).

First, the schematic I will send it to fabhouse at the end of the week end, to let me more reflexion and see your feedback:

Very basic, isn'it? You see, here, I'm taking another direction:

• direct battery, no regul so 3.3V max.
• coincell holder footprint, and two pads to connect a 2xaa/aaa holder for instance to extend the maintenance. This devices, coincell, is designed to be slim, so I would go for aaa lithium.
• Sensors : the well know SI7021 temperature/humidity, OPT3001 for the light, LHI968 PIR
• The PIR can be enabled/disabled, thx to a pmosfet
• Authentication (ATSHA204A signing)
• Radio : RFM69
• no external eeprom this time, I will use MYSBootloader on this one
• debug points for PIR circuits, no potentiometer, I will make it at hand, fixing parts values.
• reverse polarity protection

Important note : if you want to take this schematic and make your own...I hope you will take care of the routing on the PIR part because it's very important (false trigger is not far..). This part will, I'm almost sure, need some calibration. Maybe some caps could be removed but for proto I prefer to keep them. Plus it helps for reliability.

About power consumption:

You can see on the schematic few notes about this, this should give us, perhaps, roughly, 5-6uA in sleep mode with PIR enabled. No need to disable the radio (it's a camel in sleep mode + i plan to use the listenmode).

• Few simple maths because it can vary with PIR trigger, coincell quality: but for a coincell of 230mAh, I plan for 200mAh usable energy. Sleep mode :5uA, 30mA in radio transmit during says 40ms (can be more time with signing...), 10 wakeups/hour. That gives us a theoretical estimation of 2.33 years. Not so bad..It can be more if you disable pir for some periods,or less if bad software..
• that will need some software to improve the sleep mode, blind time, low power during blind time and retrigger..nice challenge

Few 3d previews, size is 49x30 (so 3 boards on a 10x5cm or 6 on a 10x10, 2mm for vcut)

Slim

One question do you prefer to have PIR High and low signals directly connected to atmel inputs, or like maybe I do, use a nanopower OR gate for one input???

If you have any remarks, I will be very happy to make some changes (basic) before ordering my pcb. Does it sound good to you?

Humm, I'm not sure, but @Samuel235 you have here an example of mosfet use to enable power if you want.

See you soon

That was yesterday..

@tekka and I tested some new features he made, so here was my humble and fun test setup

Of course the Halo GW didn't disappoint us! All boards (mixed mcus and radios nodes) were attacking it at an agressive rate (100ms rate), and there was no crash at all. Halo GW was laughing & kidding us saying "Please give me more, I like doing this" (but I was lazy to assemble more, there was 13 nodes on the table..).
Too strong @tekka

Tea time..

Here is my custom box for your RFM69 Sensebender GW ! Beautiful board though

No nail no screw

Last final minor check and i release the files, sure! (i've done one for nrf too in case..)

Hi,

I like to make my boards small as I can (with my "little" knowledge, lol) and, like lots of you I needed a small, slim and of course low power PIR sensor. I don't like chinese HC-SR504 board because there are big capacitor on it. Not easy to integrate in small enclosure. So I decided to re-design this chinese board with smd capa.
But, Anticimex pointed to me a very interesting app note : ST AN4368. Thanks to you @Anticimex for your valuable advise

Note : I ordered pcb few weeks ago, it should not take lot of time now to get them. I ordered it at oshpark, as board is small, price is cheap.

So this board is based on this ST appnote, and especially on the first schematic in it (based on TSU104 opamp, more low power).As app note state, it should be somewhere 23uA. I am using a nanopower nand gate. I didn't find better for this ref..so the board should be 1uA more. I hope it will stay between 23-25uA which is not bad I think..

I have made few changes for easy testings:

• 2x potentiometer added
• debug points
• optional led on Out Signal (for debug)

Size : 24x19.7 (mm)
Components size 0805.

Now some screenshots:

https://www.youtube.com/watch?v=Lc4ZXmKnMNw

Boards can be ordered here : https://oshpark.com/shared_projects/Dc6Tlrt1

Eagle files and BOM on my git, here : https://github.com/scalz/MySensors-HW/tree/development/LowPowerPIR_Breakout

So it should work, as I followed app note. Changes I made are minor. And I have taken care of routing to try to not have problem on analog trace...

Enjoy!

@NeverDie depends on who's old. Here in FR, yesterday, 38% of people in reanimation are <60years old. Being in reanimation, means people may also have future health consequences=money cost too.
Sadly, there are also doctors who died, infected nurses and firemen.. each day seems worse. with confinement, peak is coming very soon here I think.
Citing a french doctor: "when there is fire, you shouldn't look at the water bill"

@BearWithBeard I already got flaky 328p, a long time ago when I started with MySensors. And I decided to never buy my mcus from "unreliable" source. Especially now as I'm using advanced mcus.
I never digged what was the exact problem because I thought it was just waste of my time compared to original price. And it already wasted my time because I was searching if fault was on my side..
So I can't tell you why, but counterfeit, or out of specs, is not worth it for prod.
Sure is, reliable source always worked for me.

@NeverDie
I guess here (FR), it's quite like in others countries.. very sad.
Shutdown for two weeks at least, borders closed for 30d. Going out without a paper=penalty (130€).
Military deployed to help overwhelmed hospitals (especially in East which is epicenter here), "hopefully" I live in West. Hospitals missing protection, intubators etc..
We're a "small" country, with good healthcare, hopefully for sick people. Still It doesn't touch only old persons, there are reports of 25-40years old people deaths too.
Today, deaths have doubled here.

Personnaly, I started to limit my visits when it started in China, because I never trust when someone tells me the big cloud stopped at the borders, and didn't want to get caught and transmit to people I love..
I think govs should all have taken decisions when it started instead of waiting "will I get the flu or not??" And here we are now ..

Well, it's very sad. Praying for sick people, doctors, nurses who are on the frontline. I hope a lab will find the remedy soon.

And I hope it'll be fine for you and your family too.

@Jason-Rennie
sure, but you didn't mention the whole thing, I also prefer subghz
cr2032 is limited, so without extras capacitors = possible brownouts + you won't get full lifetime because of its internal resistance (when power consumption >5ma generally) . even a short burst can reset your mcu (brownout)
like 100-300uf to handle H version of rfm modules, I usually place a few close to batt and rf module
also forget bad coincell brands, not good at all for lifetime.
for a commercial product, I wouldn't recommend to remove brownout protection, nor watchdog too, for saving power.

I didn't know about listenmode. when I tried it worked, but this was experimental, never used it in prod.
-> custom fw with rtc and sync. simple

@Jason-Rennie unfortunately as you guessed MySensors is not really tailored for this task, so
as you don't have lot of nodes involved, perhaps it's easier to start your sw from scratch with a more simple lib+rtc, or some true mesh framework with low power capabilities if there is one available (MySensors is star network).
I guess BLE 5 long range+beacon doesn't fit your project??
imho, I think I would do my own sw, if it's just for 2-3 nodes, and sync them, perhaps easier for sw maintenance. For MySensors, we need to take care of a lot more usecases..
Long time ago, I tested rfm69 listenmode from lowpowerlab, maybe it can help you getting started.
cr2032 can be tricky, don't forget capa buffering, but that's another topic

@Jason-Rennie maybe if you give us more info on your usecase/project archi, we could help you. I think a sleeping gw is not very common.

@Jason-Rennie said in Serial gateway running on coin cells. Needs to sleep:

I think it would be better if the mysensors gateways could establish a time schedule with their nodes to allow both sides to sleep.

This is overkill for me because my system has only 1 node. But its something you might find easy to implement. I'm not sure how your system is structured.

I started to take a look at this a while ago (I wanted to try freq hop etc), but it was just tests and unfinished work, too busy to get back on this even if it's very interesting and challenge to do.. I think you don't get the implications of this. Of course it's "easy" to imagine timeslots

for a few nodes, it's not really hard, but for a whole network there are lot of things to take care.

• hardware: this needs precise clock on all devices. That's something most of MySensors users do not have, for example some use unprecise internal rtc (just an example about hw). If no precise clock, then when using lot of nodes, there will be drift in time, packets collision etc and packet delivery will become unreliable, unresponsive network.
• software. retrocompatibility is just another example. also using a better mcu (than 328p) + rtos can help managing stuff.
• etc

without retrocompatibility in mind, and by starting from scratch, it's for sure "easier" but you might hit some rocks as network grows. And, still, you will need to sync your nodes, even more important if not using a precise clock, as the wider the listening timeslot is, the more energy you'll use.

MySensors archi is gw/concentrator always ON (like many others commercial stacks though), only ONE channel communication, where availability of channel is checked with CSMA+random time+retries for preventing collisions.

there are lot of researchs about different methods like TDMA etc on internet, you'll see it's not that easy if you want more than just a few nodes

@mfalkvidd yes, hard to imagine exactly what he wants to achieve (he asked for a sleeping gw). else it's just peer2peer/node2node comm, a few people used it in the forum if I remember.

else maybe it could be easier, just using a more "simple" lib for this simple case, like radiohead etc for example

@Jason-Rennie how would you control your network from says a controller, if serial gw is sleeping? as to get power consumption down, you also need to shutdown serial hw peripheral in mcu.

@antlomb
Hello,
there are no other available RF options except RFMs and NRF in MySensors so far.
MySensors is its own RF stack. So, it's different from others RF stack like zigbee, zwave etc.