Full Networking Offload
by Bryon Moyer
March 28, 2012 at 10:14 AM
Eight months ago, Atheros (now part of Qualcomm) released a WiFi offload chip, their AR4100. It’s part of a push to enable internet-of-things applications with good-to-go 802.11b/g/n connectivity; it includes everything except the antenna. (And NVM, which is cheaper to implement with a second chip.)
They just announced some upgrades to that product, but they’ve also launched a new chip, the 4100P, which adds full networking offload. The 4100P has UDP and IPv4/v6 stacks, freeing up 60-100K of microcontroller NVM since the microcontroller no longer has to worry about this.
Meanwhile, they’ve cut down both the code store (formerly around 38K, now 24-25K) and the working memory requirements (was 11K, is now 8K) for the 4100 drivers.
While the difference between just 802.11 and UDP and IP is mostly handled in software, there apparently are some OTP settings on the chip that are different between the 4100 and the 4100P; the latter is somewhat more than simply the former with different software.
You can find more info in their release…