How can I shorten the length of the passkey?

[schosdas]

Hello

I'm using sdk v17 and trying to shorten PASSKEY.

Currently, my PASSKEY is 6 letters long. I want to shorten it to 4 letters, is this possible?

Or how do I get rid of the password I enter the first time connect to the BLE? The password for this is '0000' or '1234', but I failed both. (I removed the codes about the 'static passkey' and ran them.)
There must be a setup part for this password, but I can't found.

Can you help me with this problem?
Thank you.

[Simonr]

Hi

This passkey should be the one generated by the application and should appear between the Connected and BLE_GAP_EVT_LESC_DHKEY_REQUEST upon connecting to the device (see screenshot below). Have you by chance removed or edited the following snippet of code in your project?

        case BLE_GAP_EVT_PASSKEY_DISPLAY:
        {
            char passkey[PASSKEY_LENGTH + 1];
            memcpy(passkey, p_ble_evt->evt.gap_evt.params.passkey_display.passkey, PASSKEY_LENGTH);
            passkey[PASSKEY_LENGTH] = 0;

            NRF_LOG_INFO("Passkey: %s", nrf_log_push(passkey));
        } break;

Best regards,

Simon

[schosdas]

Aha, I think I deleted it during the passkey test.
Does that code generate passkey randomly?

What should I do to get rid of that passkey altogether? (I want to remove passkey so everyone can connect easily.)

Thank you.

[Simonr]

Indeed, this generates a 6 digit passkey for you to use for bonding. ble_app_glucose is the only example we've got that uses this passkey function as far as I am aware. You can check out the ble_app_hrs project for an example where pairing and secure connections are done without a passkey.

Best regards,

Simon

[schosdas]

Thank you!

I'll refer to it and try to revise it.