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NUS How complicated can it be...

Well - Where shall I begin? The more I look around on the web the more confused I get.

I need to create a Connection betwen a PC running Windows 10 and a sensor device server, streaming data back to the PC.

I want to use a simple UART service over BLE. Very much like the old BT 2.0 devices HC05. Providing wireless serial port emulation.

Bluetooth 5 potentially offer more than  1Mbit of data rate over the air, but all third party devices I have found shows rather sluggish performance,

even when using nRF52840, nRF52810 and similar chips that really should deliver more.

RAYTEC and FANSTEL have UART type of modules where no SOC programming is necessary . Just Rx,Tx,RTS,CTS 

But data rate is just 160kbit/s or slightly more. How can that be???  How can they waste all this capacity ???

Now - here comes my real question:

Can I use Nordics UART application NUS to circumvent these speed issues?

How do I set up the NUS communiction parameters without having to deal with SDK, compilers,Debuggers and other stuff that i'd rather not want to deal with.
RAYTEC and FANSTEL offer AT-commands for setup. Does NUS have any similar capabilities?

In other Words - How do I let a Nordig chip act as a wireless Cable. Nothing more , nothing less!

/Per

Parents
  • Hi,

    Can I use Nordics UART application NUS to circumvent these speed issues?

    Generally a practical bitrate of 160 kbit/s does not sound so bad. Theoretically you should be able to get a higher throughput, but it is affected by many things so it is difficult to say. For instance, the capabilities of mobile phones vary greatly, and many will not be able to achieve a particularly high bitrate over BLE.

    How do I set up the NUS communiction parameters without having to deal with SDK, compilers,Debuggers and other stuff that i'd rather not want to deal with.

    The SDK provide a NUS peripheral and central example, but that is exactly what it is. It is intended as a starting point so that you can develop your own application. We do not provide a production ready UART over BLE tunneling system (we might have customers who make it and sell it, but I don't know of any such end product).

    How do I let a Nordig chip act as a wireless Cable. Nothing more , nothing less!

    You develop it Slight smile

Reply
  • Hi,

    Can I use Nordics UART application NUS to circumvent these speed issues?

    Generally a practical bitrate of 160 kbit/s does not sound so bad. Theoretically you should be able to get a higher throughput, but it is affected by many things so it is difficult to say. For instance, the capabilities of mobile phones vary greatly, and many will not be able to achieve a particularly high bitrate over BLE.

    How do I set up the NUS communiction parameters without having to deal with SDK, compilers,Debuggers and other stuff that i'd rather not want to deal with.

    The SDK provide a NUS peripheral and central example, but that is exactly what it is. It is intended as a starting point so that you can develop your own application. We do not provide a production ready UART over BLE tunneling system (we might have customers who make it and sell it, but I don't know of any such end product).

    How do I let a Nordig chip act as a wireless Cable. Nothing more , nothing less!

    You develop it Slight smile

Children
  • For instance, the capabilities of mobile phones vary greatly, and many will not be able to achieve a particularly high bitrate over BLE

    And both Android and iOS put limits on the "acceptable" connection parameters - so that the theoretical limits cannot be reached.

    Also remember that a phone is a complex multi-tasking system - so it has to balance its resources amongst all the different tasks, and not let any one "hog" the system. I suspect this has something to do with why, even on the same phone, you can get different connection parameters each time you connect!

    You develop it

    Or you pay someone to develop it for you ...

  • 160 kbit not so bad??

    If we look at what  Nordic claims in their own report we should do much better than that.

    "The throughput measured may vary depending on the environment, but the maximum throughput should be around 1365 Kbps for BLE 5 High Speed, 775 Kbps for BLE 4.2, 128 Kbps for BLE 4.1 and 21.3 Kbps for BLE 5 Long Range. Be aware that there may be some inaccuracies in the measurements."

    So the question remains, why so sluggsh throughput for real UART implementations? 
    I mean, if there is no good solution, there should at least be a good excuse or expalnation! Right?..

  • Well, as that page demonstrates, the throughput very much depends on what spec you're using.

    So what spec was used for the "160 kbps" figure? If it was BLE 4.1 then it is, indeed, "not bad" !

    Note also that those figures are "maximum theoretical" - perhaps the "160 kbps" is an estimate of what's likely to be achievable in practice ?

    Did you also see the link to the BT SIG's figures: https://blog.bluetooth.com/exploring-bluetooth-5-how-fast-can-it-be

  • Yes I have seen that report earlier and it strengthen me in my belive that companies that do develop these devices (SPP clones) come up with very consevative results. (=bad designers)

    Give me a reference to a Company with a commersial Product offering >500kbit/s and I will kneel and  kiss your feet.
    I allow you to pick ANY BLE-chip. Not just Nordic!

    And I repeat: If there is no good solution, there should at least be a good excuse or explanation to why all perform so much less than theoretical! 

  • companies that do develop these devices (SPP clones) come up with very consevative results. (=bad designers)

    I think I'd rather call that "refreshing honesty" !

    But I'm still not clear where this "160kbps" comes from? Again, if it's for BLE 4.1 then it is pretty good!

    Or if it's representative of achievable, practical  rates with Android or iOS or whatever (note that those Nordic figures are between Nordic chips - not to a phone, tablet, or computer)

    Have you contacted Raytak and/or Fanstel for their comments ?

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