Hello Craig.
Saw your PCB on an other website. May you share so we can build our own RAK Concentrator Hat?
Or are you selling your PCBs?
Best regards
Jens,
Thank-you for your interest.
The website you saw the design on was most likely to be:
https://www.beyondlogic.org/rak833-lorawan-concentrator/
I’ve just updated it to include direct links to the gerbers, schematics and BOM. I’m not selling the PCBs, but you should be able to download the gerber and submit them directly to your favourite PCB house for fabrication. The BOM includes the full manufacturer part numbers. I sourced them all from Digikey.
The design was done in Circuit Maker, a free on-line PCB design tool.
https://workspace.circuitmaker.com/Projects/Details/Craig-Peacock-4/RAK833-LoRaWAN-Concentrator-Hat
If you want to change the design, you should be able to fork it from above. Circuit Maker is a tool from Altium, hence if you are familiar to Altium Designer, you should be able to pick it up easy. You can also export the design out into AD.
I just logged into my gateway. It’s been up 27 days.
Regards,
Craig
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Hello and
a big THANK YOU for that.
Regards
Jens
Why the first RAK833 and the last RAK833 is so difference? On the left hand is my first order several months ago. The right hand is my order a few weeks ago. I just have time to test and I found that the right hand does not work as expect. Poly packet forward only can detect it sometimes. The error is
INFO: Successfully contacted server 127.0.0.1
INFO: [main] Starting the concentrator
ERROR: [main] failed to start the concentrator
I found several components is missing. Are there anyone got the same as me?
Somsak
Are they both the same variant? i.e. are they both RAK833-SPI/USB-915 or just RAK833-SPI-915?
I have an early RAK833-SPI-915, but it looks like the left (two DC-DC switches). While it was purchased as a RAK833-SPI-915, the label has “Model: RAK833”
As indicated earlier in this thread, I was witnessing a higher power consumption than indicated in the data sheet. This lead me to question what the two DC-DC switches were for. I understand they are TLV62084 (device marking SLO).
The SX1301 requires a 1.8V supply, but from what I understand the SX1257/SX1255 runs exclusively on 3.3V (the input to the PCIe card). I could never work out what the other regulator was for.
The group components you highlight at the top left are behind the FT2232 USB to SPI Bridge. I’m not sure if that has any relevance. The 2nd DC-DC switcher might power something for the FT2232.
I’ve found Steven Tang (Technical contact for Rakwireless) helpful. His email is in the datasheet on the last page.
I’m testing the RAK833 on a mini pci-e to USB adapter with a pi 3B+ with raspbian stretch lite and the RAK repository below. Everything works fine for a few hours, but then the blue LED goes out and no more packets are received. The logs show that the packet forwarder process is still running and there are no errors. Has anybody else experienced this behaviour?
It feels to me like a hardware issue. I have a heatsink on the casing. When the blue LED goes out, the enclosure cools off, suggesting the module has powered off or something.
Rebooting the pi fixes the problem for another few hours.
I’ve discovered the cause is due to the usb device disconnecting and then re-connecting, suggesting a power supply or overheating issue.
I’ve used these concentrator cards for over 2 months now without issue. Used them in both the USB mode and in SPI only via a custom designed Raspberry Pi Hat. They have been performing well.
Andrew
Thanks for the response. I’ve had the module running all night on a powered USB hub, so I think it was a power issue.
Just trying to double-check what I read in these threads. Can RAK833 operate in USB-only mode without the need of SPI lanes. Is this correct and tested?
Thank you,
C
That depends. There are SPI only models and models with both SPI and USB. The later model works without SPI.
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Hi Everyone, i ma very new in this, can anyone help me with my problem, i got a RPi3B+ and RPi4 and i using RAK833 with PiSupply PCie board. i use the Balena Cloud and i manage to connect my 2 RPi to Balena Cloud but I CAN’T connect those 2 RPi in TTN network.
I just received my RAK 833 (no USB, only SPI) and am now trying to set this up with my BananaPi R2 (it has a mPCIe Connector). I’m pretty new to this and don’t really know where to start. Any hints?
SPI on an mPCIe connector is a non-standard extension, and typically not supported on mPCIe slots in single board computers (definitely not ones on PC’s!).
However it does look like your board has an SPI bus on its GPIO connector.
Essentially, look at instructions for wiring a RAK833 to a Raspberry Pi and follow those, only using the pinout of your GPIO connector.
You’ll probably end up with a different GPIO pin name for the reset line, so you’ll need to put that in the gateway reset shell script, but that shouldn’t be hard.
You should be able to get this to work, it’s just going to require some care and effort.
You will need to find something to hold the mPCIe card and tap out the SPI signals though… often you can modify an external mPCIe to USB adapter intended for mobile data cards, by very carefully soldering fine wires to the connector base (just be careful, many of them have the voltage regulators wired to run at too high a voltage!).
Or maybe you can find a physical adapter meant for a raspberry pi and do a little hobby knife surgery to adapt the GPIO. Or maybe your GPIO pinout matches a pi… not saying it does but people making ARM Linux boards based on other SoC’s have copied that before.
It’s not entirely out of the question that you could physically install the card in your SBC’s mPCIe slot but carefully use fine wires to cross-wire the USB signals to the GPIO header, it’s just that this would put your SBC board at some risk so you’d want to be good at such soldering and probably have a soldering microscope.
And no, buying the SPI model was not a mistake. The USB model uses a deprecated interface. If you really want a USB based concentrator, get the one from nFuse that uses a delegate MCU for the USB interface. But that is quirky enough that installing it in an internal slot will cause some some SBC’s not to boot…
Why did you not obtain an actually mini PCIe compatible card like the n-fuse LRWCCx-MPCIE concentrator card: https://www.n-fuse.co/devices/LoRaWAN-Concentrator-Card-mini-PCIe.html
This just requires USB signals to be routed on the mini PCI slot which us conforming to the specification, though you must check that this is the case on the host that you are using.
Well, because I thought that mPCIe is a standard and the card would “just work” with some drivers with any mPCIe Connector, because that’s why people would build something on top of a standard form factor… what does mPCIe help if its just the form factor but not using standard connections?
I also might just have bricked the RAK833 by plugging it into the mPCIe Slot of the Banana Pi R2, right?
I’m now just going to look for a Pi Hat and stick to a well tested setup. Any hints on from where to pick one up?
You’ll be surprised what you can get away with so don’t lose heart just yet.
Pi-Supply do a HAT for that board but you’ll have to ask them if they do the HAT on it’s own.
RAK actually sell an adapter board for the RAK833 to USB:
which Pi Supply have in stock:
Google may well find you one closer to where ever you are.
Those only work with the USB enabled versions of the concentrator boards. Not with the SPI only versions.
If you had purchased the USB version it would work in an mPCIe slot. However, the USB version is obsolete - it uses a a deprecated design around an FT2232 USB-SPI bridge which presents a bottleneck, and as a result you have to use an old branch of the packet forwarder software (though there are 3rd party repos that mix that with other current functionality from the current Semtech branch). Fortunately in the RAK833 the USB models also support direct SPI; in the subsequent RAK2247 they do not.
SPI on an mPCIe connector is non-standard… but direct SPI is without a doubt the best way to interface a concentrator to an embedded system which has an SPI port - anything else is just a less efficient proxy for SPI (though the efficiency loss isn’t too bad with something MCU based following from the picoGW design, as nFuse etc makes)
I also might just have bricked the RAK833 by plugging it into the mPCIe Slot of the Banana Pi R2, right?
Probably not, the SPI signals are largely on reserved pins, and to the extent that things are re-purposed they aren’t used in grossly different ways. Critical damage aspects like power pins match - which is one of the reasons you can typically do surgery on an external modem holder and add wires to make it host an SPI concentrator card. You could probably even carefully solder wires to the base of the connector on your Banana Pi to bring the SPI signals over from the GPIO port, though of course you should check the board schematic first to make sure nothing else is there.
Grrrrr, this is like nailing jello to the wall. Shoot me, shoot me now.