User's Manual

AI7688H User Manual
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Copyright@2016 AcSiP
6.8 MAC Address Rules for MBSSID
The rules of MAC address adjustment for those virtual interfaces are:
1. Modify the 2
nd
bit of the most significant byte in the MAC address to 1 to make it
as a locally administered MAC address.
2. Apply a MAC mask and add number for enumerating each interface.
The above two rules can be described as:
virtual_mac[i] = ((original_mac | 0x02 00 00 00 00 00) & mac_mask) + (i << 20)
And the mac_mask is defined as
* If BssidNum <= 2, mac_mask = 0xff ff ff ef ff ff
* If BssidNum <= 4, mac_mask = 0xff ff ff cf ff ff
* If BssidNum <= 8, mac_mask = 0xff ff ff 8f ff ff
* If BssidNum <= 16, mac_mask = 0xff ff ff 0f ff ff
For example, if the original MAC is 9C:65:F9:1B:13:62 and the current BssidNum is set to 4,
then the newly virtualized MAC address for Station mode will be:
1. Apply the locally administered bit => 9E:65:F9:1B:13:62.
2. Apply mask => 9E:65:F9:0B:13:62.
3. We only need 1 interface for Station mode, so i = 0, and this makes 9E:65:F9:0B:13:62
+ (0 << 20) = 9E:65:F9:0B:13:62.
As a result, the burned-in MAC address for AP mode (9C:65:F9:1B:13:62) will then become
9E:65:F9:0B:13:62 when it's in Station mode.
6.9 Using the Wi-Fi Dongle
AI7688H can be used as a wireless Wi-Fi router – not just for providing an Ethernet port
for Internet connection (by using a breakout board), but to provide a second Wi-Fi
interface – by using a Wi-Fi dongle (the original on-board Wi-Fi is used for the AP
connection between devices and AI7688H).This section walks you through how to install
related packages and set up system configurations for using a Wi-Fi dongle for providing
Internet connectivity on the AI7688H in AP mode. An EDIMAX Wi-Fi dongle (with Ralink