CC2530: CC2530: Group cast in ZSTACK3.0.2 & Z-Tool . Buf the delivery mode isn't GroupAddressing

user5031356

Prodigy 20 points

Part Number: CC2530
Other Parts Discussed in Thread: Z-STACK

Hello

I use the Zstack-3.0.2 and Z-Tool to test group cast.

First， I use the ZDO_EXT_ADD_GROUP to call aps_AddGroup() .

Secondlly, I use the AF_DATA_REQUEST to add two routers to the group, the response is successful.

Finally，I use the AF_DATA_REQUEST_EXT to send group cast to routers. Routers can control.

But in packet sniffer, the Delivery Mode in APS Header is Broadcast. Why not is Group Addressing?

This is screenshot of Z-Tool.

This is screenshot of the packet sniffer.

over 3 years ago

0 YiKai Chen over 3 years ago

Guru 735465 points

Ryan Brown1 Toby Pan Does TI implement group cast in network layer so it shows broadcast on APS layer?

0 Ryan Brown1 over 3 years ago

TI__Guru**** 205057 points

Hello,

This is by design, multicast messages are sent from a device to a group as a MAC broadcast message. You can refer to Section 9.8 Multicast Messages of the Z-Stack 3.0 Developer's Guide.

Regards,
Ryan

0 YiKai Chen over 3 years ago in reply to Ryan Brown1

Guru 735465 points

@Ryan, if you refer to original post of this on China E2E forum , , he posts an NXP device group command that show NXP uses 0x03 instead of 0x02. Can you help to clarify this?

0 Ryan Brown1 over 3 years ago in reply to YiKai Chen

TI__Guru**** 205057 points

Hi YK,

I have replicated this behavior on a ZNP project and noticed that Group Addressing is possible through a Sample Switch application even though the APSDE_DataReq parameters are nearly identical. I am further investigating the differences and will follow up soon.

Regards,
Ryan

0 Ryan Brown1 over 3 years ago in reply to Ryan Brown1

TI__Guru**** 205057 points

Hello all,

The reason behind this behavior is that the ZNP has multicasting enabled, this happens because the ZDO_STATE_CHANGE case is never handled (this sets _NIB.nwkUseMultiCast = nwkUseMultiCast; which is FALSE by default) in zstacktask.c since ZNP_NPI is defined. Therefore the NIB_init -> _NIB.nwkUseMultiCast = MULTICAST_ENABLED; from nwk_globals.c/h takes effect and is TRUE by default. To change this you can send a ZDO_EXT_SET_PARAMS command of value 0x80 or modify MULTICAST_ENABLED to be FALSE.

Regards,
Ryan

0 user5031356 over 3 years ago in reply to Ryan Brown1

Prodigy 20 points

Thanks Ryan

The delivery mode is group Addressing after changing _NIB.nwkUserMulticast to FALSE.Does it have an impact on other addrModes ?

0 YiKai Chen over 3 years ago in reply to user5031356

Guru 735465 points

As I know, it won't impact other address mode.

0 Ryan Brown1 over 3 years ago in reply to YiKai Chen

TI__Guru**** 205057 points

As YK stated, the multicast setting will not impact address modes other than group addressing.

Regards,
Ryan

0 YiKai Chen over 3 years ago in reply to Ryan Brown1

Guru 735465 points

Ryan Brown1 After we set MULTICAST_ENABLED to FALSE, we can see The destination address in NWK header is 0xFFFD which is broadcast type but the Multicast flash in Frame Control of NWK header shows 0 which I suppose it means Unicast. These two seem conflict. Can you help to verify and elaborate this?

We find that even set MULTICAST_ENABLED as TRUE, the device still can receive multicast command (ZCL group ON/OFF/Toggle). So, what is MULTICAST_ENABLED should be set according to Zigbee spec?

0 Ryan Brown1 over 3 years ago in reply to YiKai Chen

TI__Guru**** 205057 points

Hi YK,

The screenshot shows a group broadcast. Multicast messages can still be received with the destination address set as the corresponding group address. My recommendation is to set MULTICAST_ENABLED to FALSE but the Zigbee R22 spec allows for either method.

Regards,
Ryan

0 YiKai Chen over 3 years ago in reply to Ryan Brown1

Guru 735465 points

Ryan Brown1 How about conflict between destination address (0xFFFD) and Multicast flag (0) in Frame Control of NWK header? Is this correct? Shouldn't Multicast flag be set to 1 if the destination address is 0xFFFD which is broadcast type?

0 Ryan Brown1 over 3 years ago in reply to YiKai Chen

TI__Guru**** 205057 points

This is correct. If multicast is set to zero (using group addressing) then the destination address should be broadcast so that group addressing can be handled from the APS layer.

Regards,
Ryan

0 YiKai Chen over 3 years ago in reply to Ryan Brown1

Guru 735465 points

Ryan Brown1 Can you elaborate where I can find these information from Zigbee spec?

0 Ryan Brown1 over 3 years ago in reply to YiKai Chen

TI__Guru**** 205057 points

Hey YK,

Section 3.6.6 is Multicast Communication and Section 2.2.8 covers Functionality of the APS Sub-Layer. If you could please let me know which particular section is not clear then I will try to provide a better explanation.

Regards,
Ryan

0 YiKai Chen over 3 years ago in reply to Ryan Brown1

Guru 735465 points

Ryan Brown1 Thanks. I will check spec.

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CC2530: CC2530: Group cast in ZSTACK3.0.2 & Z-Tool . Buf the delivery mode isn't GroupAddressing