NWP Power Save Modes#
The SiWx917 NWP can be set to Power Save state via any of the Power Save Modes below based on the application use case. The NWP Power Save Modes are broadly classified into the following:
The following information outlines and analyzes the unconnected and connected state:
| Protocol | Unconnected state | Connected state |
|---|---|---|
| BLE | This mode is significant when the SiWx917 NWP/NCP device is in a standby (ideal) state. | This mode is significant when the SiWx917 NWP/NCP device is in Advertising, Scanning and Connected states. |
The SiWx917 SoC uses four internal handshake flags during Sleep and wakeup transitions between the M4 and the NWP:
TA_wakeup_M4: Set when the NWP needs the M4 to wake. Cleared when the NWP allows the M4 to enter Sleep.
TA_is_Active: Set when the NWP is in high‑power mode. Cleared when the NWP transitions to Sleep.
M4_wakeup_TA: Set when the M4 needs the NWP to wake. Cleared when the M4 allows the NWP to enter Sleep.
M4_is_Active: Set when the M4 is in high‑power mode. Cleared when the M4 transitions to Sleep.
Note: These flags are managed internally by driver APIs. Do not modify them from the application layer.