This issue was first observed on CC2642, SDK v4.10.

The first parameter of function GapScan_enable(uint16_t period, .. ) does not have any effect. Setting it to a value different than zero will not cause the scanner to scan periodically.

For example, when you use the multi_role example project and call...

GapScan_enable(8, 500, 0);

This should cause the device to scan for 5 seconds, every 10 seconds. However, the devices scans one time, gets disabled and later not re-enabled automatically.