Host Offloads To Wlan Device; Arp Offload - Infineon AIROC CYW43012 Manual

Low-power system design with AIROC™ Wi-Fi & Bluetooth® combo
chip and PSoC™ 6 MCU
WLAN power optimization techniques
wait_net_suspend (wifi,
5000, 150, 100)
Scenario#1
Scenario#2
Scenario#3
Figure 5
wait_net_suspend()
If you are using ModusToolbox™ software, see the
on using the network suspend feature safely.
See lpa middleware documentation
3.3

Host offloads to WLAN device

AIROC™ CYW43012 Wi-Fi & Bluetooth® combo chip has an Arm® Cortex®-M3 core that performs all the WLAN
device activities and supports various offloads that execute certain functionalities on behalf of the host without
interrupting the host state.
Host offloads play a key role in determining host power consumption because offloads let the host go into
Deep Sleep for extended periods of time while the WLAN device handles tasks such as 802.11 roaming, ARP,
IPv6 neighbor resolution, key rotation, and TCP keepalives on behalf of the host. In addition, these offloads free
the host CPU for other, more powerful tasks such as audio or sensor data processing. This in turn improves the
overall system efficiency and power.
The following sections describe offloads supported by AIROC™ CYW43012 Wi-Fi & Bluetooth® combo chip. The
offloads can be enabled using the Infineon low power assistant middleware. Using the LPA middleware in
ModusToolbox™ is explained in
3.3.1

ARP offload

ARP is a data link layer protocol for mapping an IP address to a physical MAC address of a device. Such mapping
is necessary for any WLAN device to keep updated on [IP:MAC] details of all nearby devices in its network. Using
the ARP protocol, a device can detect duplicate IP addresses in a network. This is also useful in notifying peer
devices of an IP address change.
Application note
Network inactive > 100 ms;
Suspend network stack
100 ms
150 ms
Window to monitor
network inactivity
Network activity detected Network
inactive < 100 ms
Do not suspend network stack
150 ms
Network inactive > 100 ms;
Suspend network stack
100 ms
150 ms
operation
mtb-example-wifi-wlan-lowpower
for additional details on these timers.
Low power assistant (LPA).
17
5000 ms
Network active
No Network activity
Network activity detected < 5000 ms
Resume network stack
code example for details
Network resumes
automatically
after 5000 ms
002-27910 Rev. *C
2023-05-29