nRF51822 example want to achieve max throughput

[Yi Su]

Hi,

I have seen several answers about how to achieve a higher data rate and I just want to make sure what I understand is correct. I am using nRF51822 chip and the dongle coming with the development board for testing right now. As I understand from the other posts, in order to get higher rate, I need to use either write commands without response or notification, set the connection interval time = 7.5ms, in this case, if I use the dongle, which only allows receiving 1 packet per connection interval, the highest data rate I can achieve will be 1(packet) * 20(Byte) * 8(bits/B) * (1/0.0075s) = 21.3kbps. If using other device that allow receiving 6 packets/connection interval, the highest data rate will be 6(packets) * 20(Byte) * 8(bits/B) * (1/0.0075s) = 128kbps.

My questions are:

1. Are my understanding and calculation above correct?

2. Are there any dongles/devices from Nordic allow 6 packets/interval receiving rate?

3. Are there any ways to increase either the number of packets transmit/receive each connection interval or the number of Bytes sent in each packet?

[Stefan Birnir Sverrisson]

1. Yes, your calculations are correct

2. Our BLE S120 cental stack is the only one we currently offer for BLE central device and it is limited to receiving rate of 1 packet per connection interval, i.e. 21 kbps. The dongle is based on the S120 so there are same limitations. We do not offer any other BLE central devices.

3. No, the central stack is limited to 1 packet per connection interval and the maximum payload in each packet is 20 bytes.

[tylernol]

is this true if we use the mbed toolchain to build our app?

[Stefan Birnir Sverrisson]

Currently, the mbed toolchain is only for the S110 stack, i.e. the peripheral device, i.e. you can only make code for a peripheral device with the mbed kit, not central device.

[tylernol]

Stefan, when will the S130 stack be available in the mbed toolchain?

[Stefan Birnir Sverrisson]

Hi have not heard of any plans for letting the mbed support more than just S110. You might speak to you Nordic's sales representative, if he/she has some more information to share.