💬 Aeos : a NRF52 versatile, up to 9in1, device
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@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..
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@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.
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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.
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@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 :)
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@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.
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@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.
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@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.
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Congratulations. Very nice concept. But I understand nothing about the range. Is it comparable with nrf24 or is it by a decade more? :)
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@Koresh
thx. I'm not sure about what you don't understand :)
If you're wondering about nrf24 vs nrf52 range, i've not tested this, i'll do that as soon as i get my custom antenna version of the board.
Because comparing a nrf24 module with pcb antenna Vs nrf52 with a chip antenna or an untuned wire antenna isn't a valid test, I think. -
@Koresh
thx. I'm not sure about what you don't understand :)
If you're wondering about nrf24 vs nrf52 range, i've not tested this, i'll do that as soon as i get my custom antenna version of the board.
Because comparing a nrf24 module with pcb antenna Vs nrf52 with a chip antenna or an untuned wire antenna isn't a valid test, I think. -
@scalz have you seen this module ?
PCB antenna + IPEX, and with 52832 we're sure it's not a clone...
At this price I can directly dump my atsamds and nrf modules :o
http://www.ebay.com/itm/nRF52832-E73-2G4M04S-Low-Power-2-4GHz-SMD-Wireless-Module-with-PCB-IPX-Antenna-/192237288810 -
@scalz have you seen this module ?
PCB antenna + IPEX, and with 52832 we're sure it's not a clone...
At this price I can directly dump my atsamds and nrf modules :o
http://www.ebay.com/itm/nRF52832-E73-2G4M04S-Low-Power-2-4GHz-SMD-Wireless-Module-with-PCB-IPX-Antenna-/192237288810 -
@Koresh
Yes, still an interesting improvement :) And i have powerful multirf boards too so..
Well i think you know it, but range is not so easy to compare, that depends on a lot of factors like datarate, ant, enclosure etc..@Nca78
yep, saw it too. I don't think they're selling clones, they looks nice ;)
Module is too big regarding my board and all what's embedded. I also wanted a stronger antenna.
This kind of meandered antenna, often the same for wire antenna though, may be prone to some detuning (regarding enclosure, environment etc.) and loosing some efficiency etc. So maybe not the full range, can be a lot less, depends (100m for this module in datasheet).But yes i agree with you :) 328p too limited, obsolete imho, "end" of nrf24 lol, and atsam is nice depending on the usecase. Personal view of course!
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@Koresh
Yes, still an interesting improvement :) And i have powerful multirf boards too so..
Well i think you know it, but range is not so easy to compare, that depends on a lot of factors like datarate, ant, enclosure etc..@Nca78
yep, saw it too. I don't think they're selling clones, they looks nice ;)
Module is too big regarding my board and all what's embedded. I also wanted a stronger antenna.
This kind of meandered antenna, often the same for wire antenna though, may be prone to some detuning (regarding enclosure, environment etc.) and loosing some efficiency etc. So maybe not the full range, can be a lot less, depends (100m for this module in datasheet).But yes i agree with you :) 328p too limited, obsolete imho, "end" of nrf24 lol, and atsam is nice depending on the usecase. Personal view of course!
@scalz said in 💬 Aeos : a NRF52 versatile, up to 9in1, device:
But yes i agree with you :) 328p too limited, obsolete imho, "end" of nrf24 lol, and atsam is nice depending on the usecase. Personal view of course!
But I think I'm still about to make one last 328 board to make a really small and low power sensor.Would you share eagle and schematic files for your prototype with the module ? I have ordered modules from EByte and I'd like some inspiration to prepare a first test board :D
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@scalz have you seen this module ?
PCB antenna + IPEX, and with 52832 we're sure it's not a clone...
At this price I can directly dump my atsamds and nrf modules :o
http://www.ebay.com/itm/nRF52832-E73-2G4M04S-Low-Power-2-4GHz-SMD-Wireless-Module-with-PCB-IPX-Antenna-/192237288810 -
@Nca78
Thanks for posting that. I just now ordered some. However, they may not arrive until September! Yowza. That means their shipping container is practically a time capsule. -
@NeverDie great ! Don't thank me I'm pretty sure I'll benefit a lot from your testing on that module :)
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One quick thing: I've started a PCB layout for this module. From the looks of the pictures on the e-bay listing, I'm assuming pins 0, 1, 2, 42, and 43 are all Ground.
Is that your interpretation also?@NeverDie said in 💬 Aeos : a NRF52 versatile, up to 9in1, device:
One quick thing: I've started a PCB layout for this module. From the looks of the pictures on the e-bay listing, I'm assuming pins 0, 1, 2, 42, and 43 are all Ground.
Is that your interpretation also?It's what's written in the datasheet ;)
0_1499826898882_E73-2G4M04S_Datasheet_EN_v1.1.pdf
