Switch Table: Basic Operation


A switch table is a set of entries to control an external antenna switch based on the current configuration of the wireless device.

There's a few things that need twiddling:

So what's it look like?

On the Atheros hardware, there'll be a common switch table and one or more antenna switch tables.

Each table has a set of output bits which are set based on the current state of the MAC/baseband, and some other configuration (eg antenna selection.) For each state, there's 'n' bits (where 'n' is the number of output bits being controlled) in that particular antenna switch table entry.

The set of MAC states generally looks something like this:

Normally the "common" switch table (shared among all radio chains) just has idle, TX, RX, bluetooth. The per-radio switch table includes the attenuation stages.

In addition, there may be different configuration settings based on whether the device is operating in 2GHz or 5GHz.

The switch table is stored in EEPROM.

Per-chipset antenna switch registers


dev/ath_hal(4)/SwitchTableBasics (last edited 2013-06-10 20:21:21 by AdrianChadd)