how can build application(transfer large data ) compatibility system/platform(android and ios)

[stevenlin]

hi all,

now i have a project which transfer data over ble to cell phone .

i do it using gatts Notifications to transfer .

for the compatibility platform(ios and android, assign mini setting) set connect interval as 30ms and packets send between connect interval 4.

ATT_MTU size 23;Connection interval 30ms; Connection event length extension (hvn_tx_queue_size) 4 and GAP event length 4

have anyone advices about this .

[Aleksander Nowakowski]

Hello!

What kind of advice are you looking for?

Sending data using notifications is easier then writing, as you don't have to artificially slow it down on older platforms. There is no buffer overflow problem. Android and iOS should receive all packets in the correct order. You may calibrate the speed by choosing connections parameters. The images you posted are valid for writing data, not receiving it. Also, they are quire outdated now.

Consider increasing interval connections and changing to higher MTU and using DLE (Data Length Extension). Then you may send less notifications, but longer, and you'll increase the speed. A sniffer is very helpful to do measurement, but you may just do some experiments and measure the time when changing to different  parameters. Keep in mind, that plder phones do not support DLE and Android 4.3 and 4.4.x support only MTU = 23.

BR, Aleksander