BLE on WB15CC (MB1641) limits notifications to 20 bytes
Dear friends, good evening.
I am facing the following problem with my application using BLE with the MB1641 (STM32WB15CC):
We had an app that worked with a device using another microcontroller (Nordic). We are adapting this device to an STM32 platform. This existing app reads the message received via Bluetooth. However, it reads the notification, not the full message.
I developed my application based on the ST example (BLE_p2pServer). However, the notification arrives in the app with 20 bytes, and we are unable to access the full buffer (although it is sent). When we use the Nordic application used for testing (nRF Connect), we see the notification with 20 bytes, and when we click on the down arrow (read), we can access the full buffer (62 bytes). In other words, the content can be sent, but we need it to be transmitted in the notification if possible.
Is there a way to change the size of the notification (let's see, the notification, not the payload itself) or is it a feature of the BLE-SIG stack implementation to transmit notifications up to 20 bytes?
We would not like to change the app, only as a last resort if necessary, to avoid costs, as the app was developed by another company.
This screen shows the notification received by Nordic MCU-based devices (complete).
This screen shows the Nordic app log. At 08:43:22 the notification was recorded (20 bytes). At 08:43:51 the message is recorded after clicking the down arrow (read with 62 bytes).
Could you help me with this question, please?
Grateful for the attention,
Wiliam
