PCI/mini PCIe concentrator boards


(PaulRB) #1

Hi all,

I am interested by Heltec HT-M01 LoRa concentrator board for €100 and have been reviewing the documentation from Heltec and @xgarb’s blog.

All the descriptions describe connecting the device to a Pi, either by SPI or USB. But I am interested to connect it (via USB) to a small server running Ubuntu 18.04 LTS. The server has a single core AMD CPU and performs various other duties (file serving, streaming music (mini-DLNA), and streaming/recording DVB TV broadcasts (TVHeadend)). The server is connected to my broadband router via a gigabit switch.

So does anyone know, or can give an opinion, if the instructions to build/install the packet forwarder onto my Ubuntu server would work?

Initially, I would attach the small antenna that ships with the M01 and the gate way would be indoors. But later I would like to use low-loss cable through the wall and attach a higher gain outdoor antenna on the outside of the building.

Thanks for any thoughts/suggestions.

Paul


Heltec HT-M01 LoRa concentrator board for €100
(Vanthome) #2

Hello Paul, in case you are using a server class host, why are you not using a device like our n-fuse LRWCCx-MPCIE card together with a proper PCI to mini PCIe adapter. This way you can embed the concentrator easily into your server.
BG, Thomas


(PaulRB) #3

Thankyou Thomas! An excellent alternative suggestion that I should consider. Can you recommend an adapter? It would need to be low profile and ideally have a pigtail or mounting hole for the pigtail’s sma socket.


(Vanthome) #4

Can you tell me the exact model of your server?, then I can suggest you something.


(PaulRB) #5

The server is home-made from old parts. The server case is 2U size (height) and the motherboard is mATX. It has 1 x PCIe x16, 1 x PCIe x4 and 2 x PCI slots. Currently, one PCI slot is occupied with a gigabit ethernet card, if I remember correctly (I will check this evening).


(PaulRB) #6

Would this is be suitable?
41PeEDu-TpL


(Vanthome) #8

Yes this is what I mean but we need to check that it’s actually compatible because it needs USB on the mini PCIe Header and I think USB is not available on the PCI bus.
This card here for example has it through a separate connector:
https://www.peak-system.com/PCIe-miniPCIe-Adapter.337.0.html?&L=1#
I saw also cheaper alternatives, need to search again…


(Vanthome) #9

This one is cheap and should work:


(PaulRB) #10

Cool. Will the pigtails that come with that card be suitable for LoRa? i.e. is the impedance required the same as is used for WiFi? I understand impedance changes with frequency, and Lora uses a lower frequency than WiFi.


(Vanthome) #11

I’m not sure what pigtails ship with this device, maybe the IPEX connector does not even fit. So if you want to be sure, just order a pigtail from our website with the device.


(PaulRB) #12

Are you referring to the PCIe adaptor card or the n-fuse card?


(Vanthome) #13

I mean the adaptor device. In the picture you can see that there are pigtails but I don’t know whether they fit.


(PaulRB) #14

Got it.

So cost-wise, this solution, including the pigtail, antenna, PCIe adaptor, tax & shipping is similar to the Heltec device. It would be a slightly neater solution, being installed into my server case.

What other advantages, if any, would the n-fuse card have over the Heltec USB device? Does it have better capabilities, better support…?


(Nestor Ayuso) #15

Don’t buy this kind of PCI adapter. It adapts PCI lanes to MiniPCIe lanes only. n-fuse uses USB interface over the MiniPCIe pins.

n-fuse is better quality than chisese Heltec. both are USB devices, both follow the same pico-gw reference design and can use the same software.


(PaulRB) #16

Thanks @nestorayuso. How can I identify PCI/PCIe adaptor with the required capability?


(Vanthome) #17

@PaulRB2 What’s wrong with the one I’ve pointed out already? Why do you need another one?


(PaulRB) #18

According to @nestorayuso, the Silverstone adaptor is not suitable because it does not support USB over PCIe lanes.

According to Silverstone,

I am confused.


(Nestor Ayuso) #19

rely in @Vanthome, he works at n-fuse, and know better than me the right adapters.

the adapter he propose seems valid, it has a four port USB hub in the board, one routed to a USB-A connector, another one routed to MiniPCIe conector and two more on pin headers.


(PaulRB) #20

But he also says

But, when I look closely at the Silverstone card, I’m not sure that the n-fuse pigtail can be fitted. I think the “pigtails” already fitted to the card cannot be removed.


(PaulRB) #21

Lycom adaptor

3017564-a

Maybe this adaptor would be more suitable? It comes with no pigtails so perhaps could accept the n-fuse pigtail? However, the card is described as “M.2”, not “Mini PCIe”. I am not expert in these differences.

@Vanthome @nestorayuso can you comment please?

EDIT: I discovered that m.2 is a different size connector to mini-pcie, so this adaptor is not suitable.