Hi,
I'm currently facing an issue with my nRF52840 chip acting as the transmitter connected to a BLE broadcasting device. One client uses a voice recorder product that requires us to subscribe to their data via a specific BLE characteristic. Currently, we can't receive the data, though the nRF Connect app on the phone works fine.
By capturing Bluetooth air packets, I discovered two key issues: First, the MTU requested by the phone is 513 bytes, far exceeding the nRF52840's maximum of 247 bytes. Second, the data volume is substantial, with each transmission containing approximately 20,000 bytes. Using nRF Connect for Desktop Bluetooth Low Energy Standalone v4.0.4 also fails. Are there any viable solutions? Should I switch chips? Or are there alternative methods to increase the MTU? Or is there some other method I haven't thought of?(I'm using SDK17 with PCA10056 -> S140)
Below is a screenshot from nRF Connect for Desktop Bluetooth Low Energy Standalone v4.0.4 showing no response. Attached is the mobile device's air packet file, viewable via WirShare. All tests were conducted using the same product model.
Looking forward to your reply.
