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PSoC 4 MCU

Anonymous
Not applicable

Hi,

   

for our current project we need a maximum data throughput for a single custom service with one characteristic (array of 4 bytes) and using the notification procedure.  

   

Now I have problems to calculate the maximum theoretical  throughput I can achieve in this case. The maximum payload size in a PDU is 27 bytes (BLE 4.1) and the minimum connection interval is 7.5ms. But how many packets are transmitted during one event ?

   

Thank you

   

Udo

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Anonymous
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I think it only sends one packet per event.

   

For your scenario, you can probably calculate it thus:

   

7.5ms connection interval, 4 bytes per packet, and 1 packet per connection interval will give:

   

4 bytes / 0.0075 s = 533.33 Bytes per second

   

Not a very fast data rate; Using a characteristic of size 20 bytes will give: 2666.66 Bytes per second

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Anonymous
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Thanks for the kind comment. But I know that the device sends more than one packet per event or interval. I guess it is in the region of 10, but I do not know the exact number.

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Anonymous
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Hmmm, guess I'm wrong then 🙂

   

I know with a sniffer (like th CySmart BLE dongle) you can actively log the packets received upon connection, with timestamps as well. Have you tried using it to log the number/data of the packets sent upon a notification?

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Anonymous
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Thanks for your tip. I will will try and report.

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