1 Reply Latest reply on Mar 1, 2018 2:37 AM by sujayy_46

    BCM43438A1: How to receive more than one packet per BLE connection interval in Central Role?

    MaRi_1281436

      I've connected a BCM434381A1 (an RedBear IoT pHAT with an Ampak AP6212A module) to my Mac over an USB-UART adapter at 921600 where I run our BTstack (http://btstack.org). I'm using the initram patch from here: https://github.com/OpenELEC/misc-firmware/raw/master/firmware/brcm/BCM43430A1.hcd

       

      When doing a performance test between the BCM and another USB Bluetooth dongle, I only receive a single packet per connection interval when the BCM is in Central Role, resulting in a mere 0.8 kB/s (200 byte ACL packets, 30 ms connection interval).

       

      If I switch roles, BCM as Peripheral and USB Bluetooth as Central, everything works fine and I'll get more than 14 kB/s (fancy!).

      Similar, with an TICC2564B instead of the BCM in the Central role, I'll also get 8.5 kB/s.

       

      I've attached logs for WireShark/Apple's PacketLogger for the both BCM tests.

       

      Did you see this before?

      Are there vendor specific events that allow to somehow reserve more buffers to allow multiple packets per connection interval?

      Should I use a different initram patch?

       

      Cheers,

      Matthias from BlueKitchen.