for my actual project I need to stream data from two devices (left, right) to an android smartphone. Desired samplerate is about 100 values per second from each device. First I tried to use the BLE112 as SoC and coded it with BGScript. For timing I used "hardware_set_soft_timer" and used the "attributes_write" method to write the data to the characteristic. The first result showed, it is possible to transfer about 95 values per second from each device. The sequence of packets and the times between (left-left and right-right) recorded with an android smartphone looks like as follows Left 8ms Right 15ms Left 15ms Right 9ms Left 20ms Right 16ms Left 1ms Right 5ms Left 9ms Right 13ms Left 15ms Right 9ms Left 10ms Right 9ms Left 5ms Left 7ms Right 14ms Right 7ms Left 15ms Right 8ms Left 8ms Right 15ms Left 15ms Right 7ms
If you use the internal ADCs (7) the samplerate goes down to 40 values per second from each device. To enhance speed, the Idea was to use an external MCU (Teensy 3.1) for ADCs and computation. This time I used the BLE112 with the BGLib implementation from Jeff Rowberg. Now I have a samplerate of about 60 values per second from each device. But the packet sequence looks like as follows. Left 47ms Left 1ms Left 1ms Right 47ms Right 1ms Right 1ms Left 47ms Left 1ms Left 1ms Right 47ms Right 1ms Right 1ms Left 47ms Left 0ms Left 1ms Right 47ms Right 0ms Right 2ms Left 48ms Left 0ms Left 1ms Right 46ms Right 1ms Right 1ms
Any idea why the packets come clustered like this?
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