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Building cc1310-based IPv6 network

Vadim Mischuk86
Intellectual 275 points
Other Parts Discussed in Thread: CC1310, CC2650, CC1350, TIMAC

Hi there, engineers. Few days ago I started working on my research - I am studying possibility of bringing 6lowPAN connectivity to some device. The target device is cc1310 and target software is Contiki OS. For this research I use two cc1310 launchpads: one acts as SLIP-radio, another - as end device. I've experimented with different examples, and the main problem for me is following: the Contiki OS documentation is pretty poor. So for now I have following questions:

1)  TI wiki says "There are three demo applications in the /examples/cc26xx directory of Contiki, hence the name they are all working on cc13xx as well as cc26xx". But when I open the cc26xx demo I se following lines:

/* Init the BLE advertisement daemon */
  rf_ble_beacond_config(0, BOARD_STRING);
  rf_ble_beacond_start();

CC1310 is not a BLE device, what is the meaning of those lines?

2) When I launch any Contiki-based code, I get following lines:

Starting Contiki-3.x-2924-g6cdba10
With DriverLib v0.46593
TI CC1310 LaunchPad
IEEE 802.15.4: No, Sub-GHz: Yes, BLE: No, Prop: No
Net: sicslowpan
MAC: CSMA
RDC: ContikiMAC, Channel Check Interval: 16 ticks
RF: Channel 25
Node ID: 47112

There are no support for 802.15.4 on 868 MHz band? All articles, I read, told me, that 6lowPAN utilizes 802.15.4 PHY and MAC layers, but from the output I see "IEEE 802.15.4: No". Anyway, what kind of PHY is used by default? 

3) Are there any guides on changing PHY parameters (for example, if I want to use UWB RF channel)?

4) Are there any ways to organize 6lowPAN network with star topology(do not use RPL) ? In my particular case using IPv6 without mesh networking would be great solution.

5)Another interesting technology is TI-15.4-STACK. But I wasn't able to find any higher level protocols (IP) realization. Are there any TI-15.4 stack-based 6lowPAN solution?

6) Another thing I dont understand in TI-15.4-STACK is frequency hopping. As far as i know, due to 802.15.4 there are only one channel available in 868 MHz band. So how is that frequncy hopping works?

Any help appreciated. Regards, Vadim.

  • 0
    Guru 735685 points
    1. You can only have BLE beacon combined in the example when you use CC2650 and CC1350 which are dual band SOC. CC1310 is single band and doesn't support BLE.
    2. It seems that you don't use latest Contiki source code. I suggest you to refer to steps in sunmaysky.blogspot.tw/.../contiki-subg-hz-6lowpan-on-cc1350.html to test again.
    3. As I know, Contiki doesn't support UWB.
    4. You can configure all your nodes to lead node and it would be star network.
    5. TI-15.4 Stack in not IPv6 based protocol.
    6. You can install TI 15.4 stack and there are developer's guide in it to explain some details.
  • 0 in reply to YiKai Chen
    Intellectual 275 points
    For a past few days have done some experiments with 6lowpan over sub1ghz and I am pretty disappointed : the data rate is very low, no matter devices are situated in one room. I was able to transmit 700 bytes of payload in about 3 seconds, which is too slow for my application. One of the reasons of such a low data rate is TCP protocol, I used , so it takes some time for handling TCP control data. Anyway are there some ways to improve data rate (e.g. using other RDC/MAC)? Maybe using CoAP over UDP can make transmittion of my data faster. The problem is that on startup boot my device must load from 5 to 50 kB of initialization data, so transmitting it over 6lowpan/TCP on such low data rates is not good solution at all. Have someone tried to launch TI 15.4 stack, I know it completely differs from 6lowPAN architecture, but maybe it can give higher data rate?
  • 0 in reply to Vadim Mischuk86
    Guru 735685 points
    As I know, you cannot increase data rate. However, you can test nullrdc to see if it is better.
  • 0
    TI__Expert 4375 points

    Hey Vadim,

    TI 15.4-Stack will allow you to achieve a higher data rate, 50kbps. Even though the network itself is not ipv6, we have an example in our SDK that shows how you can use a CC1310 LaunchPad as a Co-processor to a linux machine, such as the Beagle Bone Black. This allows the linux machine to act as a gateway. This can allows you to control the network through the central collector node from the cloud as seen in this TI Design here: http://www.ti.com/tool/tidep0084. If this looks like a solution that could work for you, I suggest you check out the TI 15.4-Stack SDK and walk through the Quick Start Guide as well as the linux examples.

    ~Brocklobsta

    Edit: TI 15.4-Stack v2.0.0 does not currently support frequency hopping in the 868MHz band; however, the next release coming soon will support it. There are 34 channels available on the 868MHz band as defined in the IEEE 802.15.4g PHY specification at 50kbps. You can refer to the specification for more details.

  • 0 in reply to Brocklobsta
    Intellectual 275 points

    Thanks for advice. I was wondering 50kbps - is it channel throughput or transfer rate of my payload?

  • 0 in reply to Vadim Mischuk86
    Guru 735685 points
    It's channel throughput.
  • 0 in reply to Brocklobsta
    Intellectual 275 points

    TI-15.4 stack seems to be quite nice solution, but does it support MTU, larger than 127 bytes? Because on such a small MTU about a half of channel throughput is wasted on control data, which is bad.

  • 0 in reply to Vadim Mischuk86
    Guru 735685 points
    As I know, it doesn't support larger than 127 bytes.
  • 0 in reply to YiKai Chen
    TI__Expert 4375 points

    127 bytes is the MTU of TIMAC on 2.4GHz, it is much higher in sub-GHz. I believe TI 15.4-Stack can support packets up to 511 bytes.

    ~Brocklobsta

  • 0 in reply to Brocklobsta
    Prodigy 20 points

    Dear 

    Above you are stating 34 channels will be used in the 868MHz band. But the ETSI EN 300 220-1 V2.4.1 states a minimum of 47 channels.

    (863 MHz to 870 MHz (see note 2) ≥ 47 at ≥ 100 kHz BW each LBT or < 0,1 % TX duty cycle (see note 1))

    How to explain this?

    Already news about the availability of the new stack release also supporting FHSS in the 868MHz?

    Are there already stacks today available for other radio chipsets supporting FHSS in the 868MHz band?

    Kind regards

    Karel