nRF5 action!
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@Mike_Lemo said in nRF5 Bluetooth action!:
@NeverDie I had mine from seeed studio
This one? https://www.seeedstudio.com/MDBT42Q-nRF52832-based-BLE-module-p-2736.html
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I was just now noticing that Nordic has a very convenient list of third party modules (and their dimensions) that use the Nordic nRF52832 chips: https://www.nordicsemi.com/eng/Products/3rd-Party-Bluetooth-low-energy-Modules
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FWIW, I just now sent an email to support@cdebyte.com requesting either a schematic of their E73-2G4M04S module itself or a schematic for a demo circuit, so that I may be certain about adding the appropriate hardware needed to get their module to work. I'll post if I hear anything back from them.
By the way, in the case of Raytac, they even have their own demo board: https://raytac.blog/2017/01/24/how-to-use-raytac-mdbt42q-nordic-nrf52832-demo-board/
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I saw this in the MDBT42Q module datasheet, and perhaps it explains the relatively poor performance of the nRF52832 Adafruit Feather which uses the MDBT42Q.:
I believe the Adafruit may have a much smaller ground plane than what is being recommended here by Raytac. -
FWIW, I just now sent an email to support@cdebyte.com requesting either a schematic of their E73-2G4M04S module itself or a schematic for a demo circuit, so that I may be certain about adding the appropriate hardware needed to get their module to work. I'll post if I hear anything back from them.
By the way, in the case of Raytac, they even have their own demo board: https://raytac.blog/2017/01/24/how-to-use-raytac-mdbt42q-nordic-nrf52832-demo-board/
I requested the schematic for the cdebyte module too...but they replied: it's confidential - LOL.
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I requested the schematic for the cdebyte module too...but they replied: it's confidential - LOL.
@mtiutiu
How long did it take them to reply to you?I guess we may have to reverse engineer what they did then--at least roughly--in order to use it. I'll see if I can pry the cover off and photograph what's inside. If I'm successful, then I'll post the photos so we can all look at it together.
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@mtiutiu
How long did it take them to reply to you?I guess we may have to reverse engineer what they did then--at least roughly--in order to use it. I'll see if I can pry the cover off and photograph what's inside. If I'm successful, then I'll post the photos so we can all look at it together.
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About 6 hours. I asked them too if the Nordic datasheet recommendations were followed or not and if they can provide an example of how to use the module.
@mtiutiu said in nRF5 Bluetooth action!:
if they can provide an example of how to use the module
What was their answer to that, or is it still pending? I don't mind them being a black box, provided they show how to use it.
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I requested the schematic for the cdebyte module too...but they replied: it's confidential - LOL.
@mtiutiu said in nRF5 Bluetooth action!:
I requested the schematic for the cdebyte module too...but they replied: it's confidential - LOL.
this one is funny, like if there was something special in their module :laughing:
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@mtiutiu said in nRF5 Bluetooth action!:
if they can provide an example of how to use the module
What was their answer to that, or is it still pending? I don't mind them being a black box, provided they show how to use it.
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Here's a photo taken from the opposite angle:
Any other photos anyone wants to see?
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Here's the back:
So, is it 4 layer as they claim, or only 2? Some of those vias seem rather pointless if it were only 2 layer. -
So, to Scalz's earlier point, it looks like indeed there is no capacitor already on DEC1. Regarding DEC2, it appears that there are pads and solder paste for a capacitor, but the capacitor appears to be missing! Manufacturing error?
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@NeverDie
cool. well you just have to check continuity.
Yes this a 4layers. better for compact RF imho, else worse performance, EMI etc.. I think it's also easier to get FCC with 4layers design (not sure if this module is FCC though)My bad, i've just reread what i wrote. With nrf52 ic, I've rechecked, I'm using:
- DEC1: 100nf
- DEC2: nothing
- DEC3: 100pf
- DEC4: 1uF (and you add inductors with DCC, for DC/DC mode but it can decrease 1dB if i remember well)
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@NeverDie
cool. well you just have to check continuity.
Yes this a 4layers. better for compact RF imho, else worse performance, EMI etc.. I think it's also easier to get FCC with 4layers design (not sure if this module is FCC though)My bad, i've just reread what i wrote. With nrf52 ic, I've rechecked, I'm using:
- DEC1: 100nf
- DEC2: nothing
- DEC3: 100pf
- DEC4: 1uF (and you add inductors with DCC, for DC/DC mode but it can decrease 1dB if i remember well)
@scalz
Both DEC3 and DEC4 appear to have capacitors on them. So, maybe it was the missing capacitor on DEC2 that's the reason for the module not seeming to work. I suppose I could crack another one open to see if the missing cap was a fluke or instead likely missing on most/all of them.Obviously, short of removing and testing each smd cap, I can't be sure as to what values eByte is using. I hope it doesn't come to that.... On the other hand, I could possibly remove and test the 3 on scalz's list that are of interest.
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OK, I just pried off the lid on a different module and.... the same DEC2 cap is missing. However, according to scalz's new list that shouldn't matter.
I'll need to check continuity to see if the DEC1 cap is really not there or rather simply appearing elsewhere due to the routing.
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OK, I just pried off the lid on a different module and.... the same DEC2 cap is missing. However, according to scalz's new list that shouldn't matter.
I'll need to check continuity to see if the DEC1 cap is really not there or rather simply appearing elsewhere due to the routing.
It turns out DEC1 is connected to a capacitor: it's the one just south of the top left capacitor in the first photo.
So, unless the cap values are just wrong, it seems that we don't need to add any more.
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What should I check next?
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I saw this in the MDBT42Q module datasheet, and perhaps it explains the relatively poor performance of the nRF52832 Adafruit Feather which uses the MDBT42Q.:
I believe the Adafruit may have a much smaller ground plane than what is being recommended here by Raytac.@NeverDie I just made the antenna on my PCB stick out so there is no fiber glass under the antenna even.
Also what is a good library for using NFC and the bluetooth peripheral of that MCU?
I came across that library:https://github.com/sandeepmistry/arduino-BLEPeripheral
but the page doesn't seem to support the BLE capability of the NRF52832
and no luck for the NFC
