nRF5_SDK_15.0.0_a53641a
s140
nRF52840
Documentation says that both ble_adv_fast_timeout and the ble_adv_slow_timeout are in units of 10ms, and that appears to be true of the latter. But when I configure a fast adv timeout, I get a longer duration than expected. The longer the timeout, the larger the discrepancy. For example:
| Desired Fast Adv Timeout | Configured Fast Adv Timeout Value | Observed Fast Adv Timeout | Percent Difference (Observed/Desired) |
| 30s | 3000 | 37s | 123% |
| 60s | 6000 | 74s | 123% |
| 180s | 18000 | 224s | 124% |
| 300s | 30000 | 373s | 124% |
| 360s | 36000 | 447s | 124% |
Configuring slow adv timeouts in the same manner yields observed timeouts in line with desired timeouts. So the behavior appears to be unique to fast advertising. We didn't notice this issue until recently when we increased our fast advertising duration during DFU advertising. Previously at a 30s timeout, the additional 7 seconds was negligible. But now at 5m, getting more than an extra minute is a bit more pronounced and concerning.
Is the documentation correct in prescribing the fast advertising timeout as being in units of 10ms?