Hi Switi, Your understanding is about right. In Nimble controller it is by default 255, but in general host gets this value using hci le read buffer size. Nimble Host reads it on startup and later expose it by ble_hs_hci_max_acl_payload_sz()
To undertand more data exchange between host and the controller over HCI I suggest to use use btmon as described here: https://www.codecoup.pl/blog/support-for-btmon-in-mynewt/ Best Łukasz On Wed, 6 Jan 2021 at 18:35, Sweety Mhaiske <sweetymhai...@gmail.com> wrote: > Hi, > > As the data between host and controller or vice versa is sent using ACL > data packet, right? > So does the size of the ACL data packet is fixed (i.e. 255 bytes) ? > > Say MTU is 512 bytes, > which means the controller will get the data packet of 512 bytes( including > header + actual data ), however when this 512 bytes of data will be sent to > the host then it will get fragmented into 255 bytes each i.e 3 packets > will be sent ( 2 packets of 255 and 1 packet of remaining data and header ) > > I want to confirm my understanding for the further development of my > project. > Waiting for your reply. > > Thanks & Regards, > Switi. >
