android - Why are there so many bluetooth profiles? -


i got started in developing bluetooth android, , keep wondering why there many bluetooth profiles , why useful?

if whole purpose of bluetooth communication send messages (bits) , forth, shouldn't core bluetooth stack have standardized way of doing without need different profiles work different types of data. mean...data streams of bits.

i working bluetooth health device profile (hdp) not bluetooth stacks implement. implement (like bluez) pass me streams of bits. not support hdp, tried listen using more generic profile spp, can't data... why?

you wondering why there many different data connection cables, since send bits.

for bluetooth profile assigns rfcomm channel number (such avrcp , hfp support profiles), can connect specified rfcomm channel number using spp, send necessary profile negotiation responses required not connection dropped, , send/receive raw data streams. of course, profile @ other end expecting "raw data" send fit profile designated format , structure.


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