How to Pair?

[erenoglu]

Question
I have a madoka thermostat using BLE and first thing you need to do is to pair. to pair it, it displays a 5 digit code and you need to click a button on the thermostat and do the same on the initiating side. The code changes each time it's paired.

How can I achieve the same in esp32-ble2mqtt? I tried the below json but it did not work. It sees the thermostat and connects but thermostat doesn't show any code as if it's not attempting any pairing/authentication.

"ble": {
"whitelist": [
"F4:93:1C:90:B9:FB", ---> This is the thermostat
"00:11:22:??:??:??" --> this one is dummy, disregard
],
"passkeys": {
"F4:93:1C:90:B9:FB": "?????", ---> I put this ????? to try to make it accept all codes but no pairing attempted
"00:11:22:??:??:??": "123456" --> this one is dummy, disregard
}
}

Additional context
I expect the esp32-ble2mqtt to attempt pairing to the whitelisted thermostat, and accept any code that it gets to complete pairing. Then normal operations can resume.

[shmuelzon]

I think the issue here is the bonding capabilities this project exposes. It currently only states that it has a keyboard (to enter a pairing code). It sound like, in this case, the pairing is expected to be done by displaying a code on both sides and clicking yes/no.

The current IO capability is set to ESP_IO_CAP_IN (which is KeyboardOnly) while it sound like we might need ESP_IO_CAP_IO (which is DisplayYesNo) or ESP_IO_CAP_KBDISP (which is Keyboard display).

If you're up for it, you can try to apply the following changes and see how it works for you:

diff --git a/main/ble.c b/main/ble.c
index db35bd8..36946bf 100644
--- a/main/ble.c
+++ b/main/ble.c
@@ -1036,7 +1036,7 @@ int ble_initialize(void)
     ESP_ERROR_CHECK(esp_ble_gattc_app_register(0));
     ESP_ERROR_CHECK(esp_ble_gatt_set_local_mtu(200));
     /* Set security IO capability to KeyboardOnly */
-    esp_ble_io_cap_t iocap = ESP_IO_CAP_IN;
+    esp_ble_io_cap_t iocap = ESP_IO_CAP_IO;
     esp_ble_gap_set_security_param(ESP_BLE_SM_IOCAP_MODE, &iocap,
         sizeof(iocap));

or

diff --git a/main/ble.c b/main/ble.c
index db35bd8..36946bf 100644
--- a/main/ble.c
+++ b/main/ble.c
@@ -1036,7 +1036,7 @@ int ble_initialize(void)
     ESP_ERROR_CHECK(esp_ble_gattc_app_register(0));
     ESP_ERROR_CHECK(esp_ble_gatt_set_local_mtu(200));
     /* Set security IO capability to KeyboardOnly */
-    esp_ble_io_cap_t iocap = ESP_IO_CAP_IN;
+    esp_ble_io_cap_t iocap = ESP_IO_CAP_KBDISP;
     esp_ble_gap_set_security_param(ESP_BLE_SM_IOCAP_MODE, &iocap,
         sizeof(iocap));