CC2640 Concurrent discover and initiate.

Thomas Engler

Other Parts Discussed in Thread: CC2640

Hello
Is it possible with the CC2640 to initiate and discover at the same time?
My goal is to be always ready to connect very fast to a upcomming slave who wants to connect with direct advertise. (whitelisted)
But also I want to receive all broadcasts from other devices.

Up to now I did not manage to realize it and I work with the following workaround:

1: Discovering

GAP_RegisterForHCIMsgs(selfEntity);                                                  //receive Broadcast & DirectAdvertise
GAP_SetParamValue(TGAP_FILTER_ADV_REPORTS, FALSE);      // do not filter advertise reports
GAPRole_StartDiscovery(DEVDISC_MODE_ALL, FALSE, FALSE);   //start scan

I do only discovering all the time to receive broadcasts and direct advertise.
(To receive the direct advertise events I changed the properties.)
When I receive a direct advetise event I go to step 2:

2: Initiating
GAPRole_CancelDiscovery();
GAPRole_EstablishLink(FALSE, FALSE, addrType, peerAddr); //connect

When the discovering receives a event from a direct advertise slave I stop discovering and I start initiating.

This solution is quite complicated and slow. Isn't it possible to discover and initiate at the same time?
I mean the radio receiver does the same if I discover or initiate. He just listen.

Thanks

over 10 years ago

0 Fredrik K over 10 years ago

TI__Guru** 106705 points

Hi Thomas,

As far as I know this is not possible. Maybe JXS has more input.

Cheers,
Fredrik

0 JXS over 10 years ago

TI__Guru** 105180 points

Hello,

If you initiate a connection to the White List, then do a scan, a connection will be initiated automatically when a white listed device is detected.

Otherwise, you will need to scan, then initiate the connection.

Best wishes

0 Thomas Engler over 10 years ago in reply to JXS

Prodigy 130 points

Hi JXS

Thanks for your respond.
I tried your suggestion:

1: Initiate with white list
----------------------------------
//prepare whitelist
HCI_LE_ClearWhiteListCmd();
for(i = 0; i<DEVICE_FILTER_LIST_SIZE; i++){
uint8 *peerAddr = &(m_DeviceFilterList[i].addr);
HCI_LE_AddWhiteListCmd( ADDRTYPE_PUBLIC, peerAddr);
}

//set filter policy & establish link
uint8_t value = GAP_FILTER_POLICY_WHITE;
GAPRole_SetParameter(GAPROLE_ADV_FILTER_POLICY, sizeof(uint8_t), &value, NULL);
GAPRole_EstablishLink(FALSE, WL_USED, 0x00, NULL);

2: Scan
-----------------
GAPRole_StartDiscovery(DEVDISC_MODE_ALL, FALSE, FALSE);

Result:
--------------
A connection with direct advertise and white list now works. Also very fast.
But I can not receive any more all broadcast events from other devices. Some I loose some I receive.
I also played arround with the scan/discover window:

GAP_SetParamValue(TGAP_CONN_SCAN_INT, u8InitiateScanInterval);
GAP_SetParamValue(TGAP_CONN_SCAN_WIND, u8InitiateScanWindow);
GAP_SetParamValue(TGAP_GEN_DISC_SCAN_INT, u8DiscoverScanInterval);
GAP_SetParamValue(TGAP_GEN_DISC_SCAN_WIND, u8DiscoverScanWindow);

Scan Window Initiate > Scan Window Discover:
--> No discover events, fast direct advertise connect

Scan Window Initiate = Scan Window Discover :
--> Sometimes discover events, sometimes slow, sometimes fast direct advertise connect

Scan Window Initiate < Scan Window Discover:
--> Receive of all discover events. No connect with direct advertise possible

Depending if the initiate or scan window is bigger or smaller discover or direct advertise works. But I never can initiate with whitelist and receive all broadcast event at the same time.

Any ideas?
Regards Thomas

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CC2640 Concurrent discover and initiate.