KB: RSL10 How to force advertising random delay to be zero

Connectivity Bluetooth Low Energy
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#1

Some customers want to use ADV as periodic data with fixed timing, maybe to transmit audio or some other type of data whose quality of service needs a fixed/known delay.

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We known this:

T_advEvent = **advInterval** + **advDelay**
  • advInterval: multiple of 0.625 ms in the range of 20 ms to 10,485.759375 s.
  • advDelay: a pseudo-random value with a range of 0 ms to 10 ms generated by the Link Layer for each advertising event

Now we have an API which can force advDelay to be zero.
BLE_DeviceParam_Set_AdvDelay(uint8_t fixedDelayEnable)

For example:
BLE_DeviceParam_Set_AdvDelay(0);
Now addDelay is a random number (between 0 ms to 10 ms)

BLE_DeviceParam_Set_AdvDelay(1);
Now addDelay is zero (0ms)

HOW TO USE:

**This API needs to be called after Bluetooth Low Energy initialization (BLE_InitNoTL(0) or BLE_Init(0)); the application is now able to force advDelay to be zero instead of a random value, allowing for an advertisement event to happen at a fixed interval.**

NOTE:

"The advDelay parameter can be set to zero instead of a random value, allowing for an advertisement event to happen at a fixed interval. This is for applications that are not Bluetooth Low Energy compliant."

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