Problem detecting 128-bit service w/ 16-bit char using BLE driver.

[Leon Woestenberg]

Setup: DK #1 is running native S110/SDK10/nRF51, one service 128-bit w/ 16-bit char:

Service UUID: 0x0xb1ad
Service UUID type: 0x0x2
Service handle: 0x0x0c
Service handle: 0xc
Characteristic value handle: 0xe
Characteristic CCCD handle: 0xf

DK #2 is running S130 serialization with Linux driver, modified HRM collector:

Received service discovery response

UUID: 0xB1AD, start handle: 0x000C, end handle: 0xFFFF
Discovering characteristics
Received characteristic discovery response, characteristics count: 1
Handle: 0x000D, UUID: 0xBEEF
Discovering descriptors
Received descriptor discovery response, descriptor count: 1
Handle: 0x000D, UUID: 0x2803
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Unhandled event with ID: 81

The service and char are correctly detected, but somehow the characteristic descriptor is not (handle 0x000D is returned twice.)

What could the cause be?

How can I find the problem to be on the peripheral or central? LightBLUE app on iPhone shows a descriptor and notify works on the characteristic, so I assume the descriptor is setup alright.

[Leon Woestenberg]

By pure luck I found this patch lurking in the pc-ble-driver-py folder /usr/local/lib/python2.7/dist-packages/pc_ble_driver_py/hex/SD20_SDK11.patch, which seems a likely candidate for a fix of the (wrong) behaviour I am seeing:

diff --git a/components/serialization/application/codecs/s130/middleware/app_mw_ble_gatts.c b/components/serialization/application/codecs/s130/middleware/app_mw_ble_gatts.c
--- a/components/serialization/application/codecs/s130/middleware/app_mw_ble_gatts.c
+++ b/components/serialization/application/codecs/s130/middleware/app_mw_ble_gatts.c
@@ -586,7 +586,8 @@ static uint32_t gatts_attr_get_rsp_dec(const uint8_t * p_buffer, uint16_t length
     const uint32_t err_code = ble_gatts_attr_get_rsp_dec(
         p_buffer,
         length,
-        (ble_gatts_attr_md_t **)&mp_out_params[0],
+        (ble_uuid_t **)&mp_out_params[0],
+        (ble_gatts_attr_md_t **)&mp_out_params[1],
         &result_code);

[Leon Woestenberg]

This is no bug fix for the issue I am seeing. Instead I am now going to try the SD 2.0.1 that comes with the pc-ble-driver-py release which has a newer SD 2.0.1, newer lib/includes and SDK11 patch.