Added Peer Manage to ble_app_blinky

[kai19960504]

Hi All,

I want to add pairing and binding functions to the blinky project.

But nothing happens when I connect.

Please help me,thank you.

Here is my project => Lab10_PeerManager_pairing.zip

I'm using SDK v17.1.0

Best regards,

Kai

[Einar Thorsrud]

Hi Kai,

I had a biref look at your project and see one issue that is clearly incorrect. In your handling of the BLE_GAP_EVT_SEC_PARAMS_REQUEST you reply that pairing is not supported. You need to remove this. In fact, there is no need to handle this event at all, as it is handled by the peer manger library.

Einar

[kai19960504]

Hi Einar,

Finally I refer to the example of gls.

I observed that pairing needs to use these few lines of code =>

err_code = pm_conn_secure(p_ble_evt->evt.gap_evt.conn_handle, false);
            if (err_code != NRF_ERROR_BUSY)
            {
                APP_ERROR_CHECK(err_code);
            }

Now I have two questions : 1. why bps example does not use this API.

                                            2. My program has a pairing function after adding that API, but the phone will jump 2 times to                                                      notify before it can be connected.

Best regards,

Kai

[kai19960504]

Hi Einar,

Is there any news?

[Einar Thorsrud]

Hi,

I am sorry for the late reply (there has been Easter holiday in Norway so DevZone has had reduced staffing).

kai19960504 said:

1. why bps example does not use this API.

The call to pm_conn_secure() ins used to initiate security on the link, either pairing if it is the first time, or just encrypting the link if an old bond exists. If the peer initiates security (which is often the case if it is for instance a mobile phone), then this is not needed.

kai19960504 said:

2. My program has a pairing function after adding that API, but the phone will jump 2 times to                                                      notify before it can be connected.

I do not full understand what this is. Can you elaborate?

[kai19960504]

Hi Einar,

Einar Thorsrud said:

I do not full understand what this is. Can you elaborate?

I think you can refer to my current project and actually connect with the mobile phone to see what I mean.

Projects to be tested => 7652.Lab10_PeerManager_pairing.zip

Another problem is that when I remove the lines of main.c (509~513), the pairing function will not work.

// Kai
err_code = pm_conn_secure(p_ble_evt->evt.gap_evt.conn_handle, false);
if (err_code != NRF_ERROR_BUSY)
{
    APP_ERROR_CHECK(err_code);
}
// Kai

Best regards,

Kai

[Einar Thorsrud]

Hi Kai,

I tested your project briefly (just connecting and pairing) and that seems to work as expected. With the unmodified project, I connect, and then the nRF initiates pairing and that proceeds successfully when I test with an iPhone with the nRF Connect app.

After commenting out the call to pm_conn_secure() the nRF no longer initiates pairing, so that is now up to the central. iOS only pairs when needed (after not being allowed to access a characteristic due to too low security level). So in order to make the iPhone pair I did a small change to your LBS service so that reading or writing to the button or LED requires security, and thus makes the iPhone pair:

Fullscreen ble_lbs.c.diff Download

diff --git a/ble_lbs/ble_lbs.c b/ble_lbs/ble_lbs.c
index f2a72f9..c255ede 100644
--- a/ble_lbs/ble_lbs.c
+++ b/ble_lbs/ble_lbs.c
@@ -107,8 +107,8 @@ uint32_t ble_lbs_init(ble_lbs_t * p_lbs, const ble_lbs_init_t * p_lbs_init)
     add_char_params.char_props.read   = 1;
     add_char_params.char_props.notify = 1;
 
-    add_char_params.read_access       = SEC_OPEN;
-    add_char_params.cccd_write_access = SEC_OPEN;
+    add_char_params.read_access       = SEC_JUST_WORKS;
+    add_char_params.cccd_write_access = SEC_JUST_WORKS;
 
     err_code = characteristic_add(p_lbs->service_handle,
                                   &add_char_params,
@@ -127,8 +127,8 @@ uint32_t ble_lbs_init(ble_lbs_t * p_lbs, const ble_lbs_init_t * p_lbs_init)
     add_char_params.char_props.read  = 1;
     add_char_params.char_props.write = 1;
 
-    add_char_params.read_access  = SEC_OPEN;
-    add_char_params.write_access = SEC_OPEN;
+    add_char_params.read_access  = SEC_JUST_WORKS;
+    add_char_params.write_access = SEC_JUST_WORKS;
 
     return characteristic_add(p_lbs->service_handle, &add_char_params, &p_lbs->led_char_handles);
 }

(This change is not needed when using Android or nRF Connect for Desktop, where you can force pairing as you like).

[kai19960504]

Hi Einar,

I'm using Android.

Einar Thorsrud said:

(This change is not needed when using Android or nRF Connect for Desktop, where you can force pairing as you like).

It cannot match.

[Einar Thorsrud]

I am not able to see any issue in that case. Can you try to explain with words what the problem is, how you test and in what way it does not work?

[kai19960504]

Hi Einar,

Einar Thorsrud said:

So in order to make the iPhone pair I did a small change to your LBS service so that reading or writing to the button or LED requires security, and thus makes the iPhone pair:

I tested it not long ago, and Android also needs this setting to have the pairing function appear.

Now my doubts are resolved, but there is still one question I don't understand.

Why does pm_conn_secure() need to be paired twice?

[Einar Thorsrud]

Hi,

kai19960504 said:

I tested it not long ago, and Android also needs this setting to have the pairing function appear.

It needs it for pairing to appear automatically, yes (because it needs to be initiated form one side, and if the phone does not do it one way or another, the nRF must). But pairing works regardless, just that it must be initiated in a different way. Also, there is not much point in pairing without also requiring security on some characteristics.

kai19960504 said:

Why does pm_conn_secure() need to be paired twice?

What do you mean? The function just initiates pairing, it works the same every time (that said, if bonded already, it will just initiate encryption of the link using existing key. If not bonded, it will initiate pairing).

[kai19960504]

Hi Einar,

Einar Thorsrud said:

What do you mean? The function just initiates pairing, it works the same every time (that said, if bonded already, it will just initiate encryption of the link using existing key. If not bonded, it will initiate pairing).

You can refer to this link.

The statement is a problem with Android itself. If it is actually applied to the product, will the same situation happen?