💬 Aeos : a NRF52 versatile, up to 9in1, device
-
To clarify a bit why there are two revisions, i prefer to be transparent ;) And i'm interested in your feedbacks!
I won't talk about the prototype which has no sensors onboard. I designed revision 1, because i wanted to have sensors onboard and to have choice during assembly.
I was curious to know the range of these modules. Made two different boards to compare layout. Followed the guidelines, tried to optimize gnd plane etc..
Simple test was :
- chip antenna not big range. Interesting i could cover almost the house, but at some spots i lost a few packets. not enough acceptable for me, or that depends when I would place it.
Ok let's verify what i'm thinking.
Unsoldered the chip antenna, and soldered a 31mm monopole antenna in place. Even if it wouldn't get so well tuned because of the hack, bingo, i almost doubled my range.
Grrr, but the board is sexy like that. Ok, why leaving it then :) - So i designed revision 2, for a better RF version. But it's a different layout, with more pinouts. I don't think that will be a problem on my side to use an adapter 1.27mm to 2.54 for reprogramming etc.. especially when there will be some OTA feature
Both boards have their pros and cons, so i keep both, that will depend on my usecases.
- chip antenna not big range. Interesting i could cover almost the house, but at some spots i lost a few packets. not enough acceptable for me, or that depends when I would place it.
-
To clarify a bit why there are two revisions, i prefer to be transparent ;) And i'm interested in your feedbacks!
I won't talk about the prototype which has no sensors onboard. I designed revision 1, because i wanted to have sensors onboard and to have choice during assembly.
I was curious to know the range of these modules. Made two different boards to compare layout. Followed the guidelines, tried to optimize gnd plane etc..
Simple test was :
- chip antenna not big range. Interesting i could cover almost the house, but at some spots i lost a few packets. not enough acceptable for me, or that depends when I would place it.
Ok let's verify what i'm thinking.
Unsoldered the chip antenna, and soldered a 31mm monopole antenna in place. Even if it wouldn't get so well tuned because of the hack, bingo, i almost doubled my range.
Grrr, but the board is sexy like that. Ok, why leaving it then :) - So i designed revision 2, for a better RF version. But it's a different layout, with more pinouts. I don't think that will be a problem on my side to use an adapter 1.27mm to 2.54 for reprogramming etc.. especially when there will be some OTA feature
Both boards have their pros and cons, so i keep both, that will depend on my usecases.
- chip antenna not big range. Interesting i could cover almost the house, but at some spots i lost a few packets. not enough acceptable for me, or that depends when I would place it.
-
What I especially like is the small size: 33x33mm. By comparison, Nordic's 52 Thingy is ginormous.
Do OTA sketch uploads work? That would be another very nice asset for anyone who wants to play around with it.
-
Wow again, this will make a pretty impressive platform for multi sensors and/or for advanced sensors. Microphone is a great addition for that with the processing power available.
You should make a Bluetooth version of that with a half baked smartphone app, with good marketing on kickstarter you can get rich :D
As you are usually obsessed with the extra uA to trim, I'm a bit surprised with your choice of hall sensor, did you miss the TI DRV5032 ? It costs peanuts and uses just 1/3 of the current compared to the Honeywell you have chosen.
-
@NeverDie
same here :)
OTA, with ble or not, in MySensors is not done yet. But i'm not playing alone with Aeos ;)@Nca78
thx! Yep, that would be a lot of fun! don't tempt me too much with things like that! For the moment project is in progress, let's see if i feel there are interests, and if my RF board will be ok too but i have good hope. Of course, i'll do a simple mobile app for fun, asap!Lol, you got me! I missed this nice TI ref, you're right, thx :+1: They are same footprints, so not a problem.
Also, with Aeos main board or the extension, it is possible to use a reed switch instead, and get no power consumption in both states (i've another project, and proto is working ok, will show this soon!, ). -
@NeverDie
same here :)
OTA, with ble or not, in MySensors is not done yet. But i'm not playing alone with Aeos ;)@Nca78
thx! Yep, that would be a lot of fun! don't tempt me too much with things like that! For the moment project is in progress, let's see if i feel there are interests, and if my RF board will be ok too but i have good hope. Of course, i'll do a simple mobile app for fun, asap!Lol, you got me! I missed this nice TI ref, you're right, thx :+1: They are same footprints, so not a problem.
Also, with Aeos main board or the extension, it is possible to use a reed switch instead, and get no power consumption in both states (i've another project, and proto is working ok, will show this soon!, ).@scalz yes I have done the thing with the normally opened + normally closed switch for my entry door and after over 1 year voltage drop is only minimal on a Chinese CR2032. But I'm not a huge fan a the reed switch as they break too easily especially the NO+NC versions with 2 pins on the same side.
For the hall switch it seems it's new, Honeywell has to update it's docs about having the lowest power consumption :D
-
@Nca78
i agree. reed switch need some care during assembly ;) that's why i added hall effect.
yep, honeywell aren't the lowest power consumption anymore, 1.8 still not so bad. Hopefully, the better TI sensor is footprint compatible. Just need to order some. -
As a future challenge for somebody, do you think a feature reduced version could be size reduced to a 23x23mm PCB? That's the size of the am612 PIR lens, and it would be a lot of fun to have a functioning wireless PIR sensor that's at the limit of super tiny.
-
As a future challenge for somebody, do you think a feature reduced version could be size reduced to a 23x23mm PCB? That's the size of the am612 PIR lens, and it would be a lot of fun to have a functioning wireless PIR sensor that's at the limit of super tiny.
Looks as though 23mmx24.5mm, not 23mmx23mm, might (?) be the limit on PCB size because of the bore-holes for attaching the PIR lens.
-
@NeverDie
hehe :)For PIR and battery, i have a preference for the bigger CR2450.
I will use CR2032 for simple low power sensors everywhere i need variants of them, and they will all look the same shape.
Then, I had to choose a coincell holder. regarding thickness, and size etc.And the most important point for the board : the antenna.
PIR isn't a wearable (i exagerate, but wearable meaning short range), or a simple sensor reporting x min.
Which antenna vs range ? Also, the clearance of the antenna (nothing under it..). GND plane size..So the coincell holder and the antenna requirements almost fix the pcb size.
I could choose a smaller but less efficient antenna, which would need more tuning, or could be prone to detuning regarding different enclosure and usecases. That could reduce the board size of a few mm.
Instead i've decided to bet on a more efficient antenna, so less debug (only have a spectrum analyzer..).I thought : aestetically or discretion, of course I didn't want 40x40 board, but does it really matter to me if my board is 25x30 or 33x33 ?? Am i doing the contest of the smallest wearable PIR ? :)
(saying this because, indeed, i previously designed a smaller board for PIR, but chip antenna, smd PIR+dedicated lens=more expensive, and there wasn't pinheaders, just programming pads. less versatile. Whereas, I can hack Aeos and extend it).That plus some others variables, made me choose for this shape..
-
@NeverDie
hehe :)For PIR and battery, i have a preference for the bigger CR2450.
I will use CR2032 for simple low power sensors everywhere i need variants of them, and they will all look the same shape.
Then, I had to choose a coincell holder. regarding thickness, and size etc.And the most important point for the board : the antenna.
PIR isn't a wearable (i exagerate, but wearable meaning short range), or a simple sensor reporting x min.
Which antenna vs range ? Also, the clearance of the antenna (nothing under it..). GND plane size..So the coincell holder and the antenna requirements almost fix the pcb size.
I could choose a smaller but less efficient antenna, which would need more tuning, or could be prone to detuning regarding different enclosure and usecases. That could reduce the board size of a few mm.
Instead i've decided to bet on a more efficient antenna, so less debug (only have a spectrum analyzer..).I thought : aestetically or discretion, of course I didn't want 40x40 board, but does it really matter to me if my board is 25x30 or 33x33 ?? Am i doing the contest of the smallest wearable PIR ? :)
(saying this because, indeed, i previously designed a smaller board for PIR, but chip antenna, smd PIR+dedicated lens=more expensive, and there wasn't pinheaders, just programming pads. less versatile. Whereas, I can hack Aeos and extend it).That plus some others variables, made me choose for this shape..
There is, of course, no single perfect solution for everything. Once you start pushing the limits, the trade-offs start to become more apparent.
That's what makes this an interesting hobby! :)One could possibly cheat the coincell holder issue by using a tabbed coincell. That may or may or be a desirable trade-off, depending on your goal, but it might free up some real-estate. Maybe if the antenna could somehow be pasted onto or formed into the enclosure box, maybe that would work too. Just trying to figure out if there might be any ways around the obstacles you've noted above.
-
To clarify a bit why there are two revisions, i prefer to be transparent ;) And i'm interested in your feedbacks!
I won't talk about the prototype which has no sensors onboard. I designed revision 1, because i wanted to have sensors onboard and to have choice during assembly.
I was curious to know the range of these modules. Made two different boards to compare layout. Followed the guidelines, tried to optimize gnd plane etc..
Simple test was :
- chip antenna not big range. Interesting i could cover almost the house, but at some spots i lost a few packets. not enough acceptable for me, or that depends when I would place it.
Ok let's verify what i'm thinking.
Unsoldered the chip antenna, and soldered a 31mm monopole antenna in place. Even if it wouldn't get so well tuned because of the hack, bingo, i almost doubled my range.
Grrr, but the board is sexy like that. Ok, why leaving it then :) - So i designed revision 2, for a better RF version. But it's a different layout, with more pinouts. I don't think that will be a problem on my side to use an adapter 1.27mm to 2.54 for reprogramming etc.. especially when there will be some OTA feature
Both boards have their pros and cons, so i keep both, that will depend on my usecases.
@scalz said in 💬 Aeos : a NRF52 versatile, up to 9in1, device:
Great device. The next generation nRF5 has a USB serial device included. When you add D+ and D- to the USB Board/Main Board interface the next nRF5 can act as Gateway. -> http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52840.ps/usbd.html?cp=2_0_0_50#concept_usb_fp
Unsoldered the chip antenna, and soldered a 31mm monopole antenna in place. Even if it wouldn't get so well tuned because of the hack, bingo, i almost doubled my range.
Do you have used an simple wire or something else?
- chip antenna not big range. Interesting i could cover almost the house, but at some spots i lost a few packets. not enough acceptable for me, or that depends when I would place it.
-
@d00616
thx! Yep, i've noticed the usb feature too, and i'm waiting for a better availability ;) (i've already designed a test dongle for fun, not ordered the pcb yet)regarding my simple test with chip antenna modules, yes i've used a simple wire, the same i use with my rfm69 : one 0.57mm solid core, and 31mm length for nrf. (diameter of the solid core shouldn't matter a lot i think). I have good hope to get an even better range with the pcb antenna. I'll keep you informed of course :)
-
@scalz Will your Aeos be communicating with another NRF52? Do you already have code for that? Or will it be connecting with a phone over bluetooth, which is what I'm just now discovering is what most of the existing demo code for the NRF52 seems to focus on.
-
@NeverDie
yes sure. For example, in Mysensors, I have now 4x nrf52 nodes (aeos and other custom boards) talking to esp32+nrf24 gw.So, NRF52 <-> NRF52 and NRF52 <-> NRF24 are working well, and you can simply use Mysensors examples and set the defines, that's all, nothing more to do, it's transparent. Thx to the Mysensors NRF52 ESB port, pretty cool.
For bluetooth, I've started to take a look for a simple BLE phone app too, for fun. That said with BLE available, we could get nice features in Mysensors..
Finally, little sidenote about my simple range tests. They were quick, not in ideal conditions, but gave me an indication.
I have tested BLE and Mysensors modes. Power supply for the node was 2x fresh AAA battery:- as a BLE beacon, and was checking the rssi with a phone app. Not a precise test as rssi is not linear.
- with Mysensors. A simple counter was sent to the gw and i was looking for missing packet.
I'll do more tests of course because some variables can change the results (like if it is in enclosure depending of wire antenna or not, orientation ..). For example, I will check pcb antennas by testing communication between two identical nodes.
-
@NeverDie
yes sure. For example, in Mysensors, I have now 4x nrf52 nodes (aeos and other custom boards) talking to esp32+nrf24 gw.So, NRF52 <-> NRF52 and NRF52 <-> NRF24 are working well, and you can simply use Mysensors examples and set the defines, that's all, nothing more to do, it's transparent. Thx to the Mysensors NRF52 ESB port, pretty cool.
For bluetooth, I've started to take a look for a simple BLE phone app too, for fun. That said with BLE available, we could get nice features in Mysensors..
Finally, little sidenote about my simple range tests. They were quick, not in ideal conditions, but gave me an indication.
I have tested BLE and Mysensors modes. Power supply for the node was 2x fresh AAA battery:- as a BLE beacon, and was checking the rssi with a phone app. Not a precise test as rssi is not linear.
- with Mysensors. A simple counter was sent to the gw and i was looking for missing packet.
I'll do more tests of course because some variables can change the results (like if it is in enclosure depending of wire antenna or not, orientation ..). For example, I will check pcb antennas by testing communication between two identical nodes.
