I am a newbie to Nordic chips and tools and new to bluetooth. My company is doing a BLE sensor. We have a prototype board ready and I am trying to do some firmware for it.
My boss gave me a copy of development environment, which a previous employee in my company used for nRF51822 but with different sensor. So basically it is almost same for the firmware development view. I have tried to modified the existing code to feed it with fake sensor data, compile the existing code. According to what my boss told me, I firstly burnt the S110 softDevice, then compile and download the firmware to 51822 in MDK-5. It works ! I could receive the fake sensor data through BLE GATT characteristic notification values on Bluetooth Reader and other tools. The only problem is that the data throughput is very low.
I used a very simple loop to send Gatt notifications, got fewer than notifications per second, or only less than 400 Bytes/second.
The general firmware loop is as following:
void sendOnePacketToBle(unsigned char *pData, int len)
{
while(1)
{
if(ble_nus_string_send(&m_nus, pData, len) == NRF_SUCCESS)
{
break;
}
delay();
}
}
main()
{
unsigned char[] sampleData={'0','1','2','3''4','5'};
while(1){
sendOnePacketToBle(sampleData, 6);
}
}
I am curious why the throughput is so low. Is it related to the SDK or SoftDevice? 
Does the SoftDevice need any configuration to get a higher throughput? If yes, could you tell me how to do it?
By the way, is there any way to know which SDK version I am using in this development platform? I am curious whether it is possible to change to any other SoftDevice version, and how to change it.
Thanks,
Jun
