Data transfer time in a state when several peripheral devices are connected to one central

[Filya]

Hi

Please help me sort out one question.

I have a peripheral device that stores an archive with data. At a certain point, the archive is transferred to the central device (android device) and the transfer takes ~ 3.5 seconds. Everything is fine here.

Then I tried to connect several peripheral devices to one central device at once and transfer archive data from only one device. The transfer took longer. For example, if only 3 peripheral devices were connected, then transferring the archive from one device takes ~ 8.5 seconds. If you add more devices, the time increases accordingly (it is interesting that the time increases proportionally by 2.5 seconds for each new connected device). The question is, why is the transmission time, from only one device, increasing? Perhaps the appeal of the central device goes in turn to each peripheral and this creates a delay?

Thanks in advance for your help.

[Sigurd]

The central need to spend radio time to maintain and keep the other BLE connections alive. Your peripheral need to share this radio time with the other peripherals, the data throughput will therefore be lower, and it will take more time to finish the transfer.