WEBENCH® Tools/CC2541: Pairing Process

Muqarrab Rahman

Part Number: CC2541

Tool/software: WEBENCH® Design Tools

Hi,
I am using cc2541. I am working on the pairing process. I am using the following commands and successfully able to pair device by entering
123456 code.

// Setup the GAP Bond Manager
{
uint32 passkey = 123456; // passkey "000000"
uint8 pairMode = GAPBOND_PAIRING_MODE_WAIT_FOR_REQ;
uint8 mitm = TRUE;
uint8 ioCap = GAPBOND_IO_CAP_DISPLAY_ONLY;
uint8 bonding = TRUE;
GAPBondMgr_SetParameter( GAPBOND_DEFAULT_PASSCODE, sizeof ( uint32 ), &passkey );
GAPBondMgr_SetParameter( GAPBOND_PAIRING_MODE, sizeof ( uint8 ), &pairMode );
GAPBondMgr_SetParameter( GAPBOND_MITM_PROTECTION, sizeof ( uint8 ), &mitm );
GAPBondMgr_SetParameter( GAPBOND_IO_CAPABILITIES, sizeof ( uint8 ), &ioCap );
GAPBondMgr_SetParameter( GAPBOND_BONDING_ENABLED, sizeof ( uint8 ), &bonding );
}

NOW my question is how can I pair directly without entering that code?
As some Bluetooth devices initialize pairing request and we just accept request and device become paired.
How can I do that in cc2541?

Thanks!

over 4 years ago

0 Muqarrab Rahman over 4 years ago

Expert 2580 points

Any suggestions, please?

0 Eirik V over 4 years ago in reply to Muqarrab Rahman

TI__Guru 56590 points

Hello Muqarrab,

You are looking for justWorks pairing.

// Setup the GAP Bond Manager
{
uint32 passkey = 0; // passkey "000000"
uint8 pairMode = GAPBOND_PAIRING_MODE_WAIT_FOR_REQ;
uint8 mitm = FALSE;
uint8 ioCap = GAPBOND_IO_CAP_NO_INPUT_NO_OUTPUT;
uint8 bonding = TRUE;
GAPBondMgr_SetParameter( GAPBOND_DEFAULT_PASSCODE, sizeof ( uint32 ), &passkey );
GAPBondMgr_SetParameter( GAPBOND_PAIRING_MODE, sizeof ( uint8 ), &pairMode );
GAPBondMgr_SetParameter( GAPBOND_MITM_PROTECTION, sizeof ( uint8 ), &mitm );
GAPBondMgr_SetParameter( GAPBOND_IO_CAPABILITIES, sizeof ( uint8 ), &ioCap );
GAPBondMgr_SetParameter( GAPBOND_BONDING_ENABLED, sizeof ( uint8 ), &bonding );
}

0 Muqarrab Rahman over 4 years ago in reply to Eirik V

Expert 2580 points

Thanks, Eirik V,
.

I have successfully able to pair device without pairing key by changing the above commands.

BUT

now unable to read/write characteristics.(Having this property GATT_PERMIT_AUTHEN_READ | GATT_PERMIT_AUTHEN_WRITE,)

Can you suggest a solution how can read/write now?

0 Muqarrab Rahman over 4 years ago in reply to Muqarrab Rahman

Expert 2580 points

Any suggestion, please?

0 Eirik V over 4 years ago in reply to Muqarrab Rahman

TI__Guru 56590 points

Hello Muqarrab,

You need to enable MITM to have an authenticated link.

The input and output capabilities of the devices in the pairing request must match to make authentication is possible.

0 Muqarrab Rahman over 3 years ago in reply to Eirik V

Expert 2580 points

Hi Eirik V,

I am setting the following parameters but still unable to READ/WRITE characteristics.
What should I do now?

// Setup the GAP Bond Manager

{
uint32 passkey = 123456; // passkey "000000"
uint8 pairMode = GAPBOND_PAIRING_MODE_WAIT_FOR_REQ;
uint8 mitm = TRUE;
uint8 ioCap = GAPBOND_IO_CAP_NO_INPUT_NO_OUTPUT;
uint8 bonding = TRUE;
GAPBondMgr_SetParameter( GAPBOND_DEFAULT_PASSCODE, sizeof ( uint32 ), &passkey );
GAPBondMgr_SetParameter( GAPBOND_PAIRING_MODE, sizeof ( uint8 ), &pairMode );
GAPBondMgr_SetParameter( GAPBOND_MITM_PROTECTION, sizeof ( uint8 ), &mitm );
GAPBondMgr_SetParameter( GAPBOND_IO_CAPABILITIES, sizeof ( uint8 ), &ioCap );
GAPBondMgr_SetParameter( GAPBOND_BONDING_ENABLED, sizeof ( uint8 ), &bonding );
}

Thanks!

0 Eirik V over 3 years ago in reply to Muqarrab Rahman

TI__Guru 56590 points

Hello Muqarrab,

Please refer to table Table 2.8: Mapping of IO capabilities to key generation method in the BLE Core Spec 5.1.

ioCap of GAPBOND_IO_CAP_NO_INPUT_NO_OUTPUT end up with justWorks which is not authenticated (Unauthenticated).

0 Muqarrab Rahman over 3 years ago in reply to Eirik V

Expert 2580 points

Thanks Eirik V,

Can you please provide the mentioned document or link from where I can download.

I have many other documents but unable to find the mentioned topic.

Thanks!

0 Eirik V over 3 years ago in reply to Muqarrab Rahman

TI__Guru 56590 points

The latest (5.2) is listed here:

https://www.bluetooth.com/specifications/bluetooth-core-specification/

Table 2.8: Mapping of IO capabilities to key generation method

Bluetooth®︎

Bluetooth forum

WEBENCH® Tools/CC2541: Pairing Process