Rainbow Electronics AT86RF211 - Manual (Page 2)

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AT86RF211
1942C–WIRE–06/02
General Overview
General Overview of
Functioning The AT86RF211 is a microcontroller RF peripheral: all the user has to do is to write/read
registers to setup the chip (i.e. frequency selection) or have information about parame-
ters such as RSSI level, Vbattery, PLL lock state. All these operations are carried out via
a three-wire serial interface.
Normal Mode The chip is set-up by the microcontroller: frequency and mode (Rx or Tx). Then it acts
like a "pipe": any data entering DATAMSG is immediately radiated (Tx) or any wanted
signal collected by the aerial is demodulated, transferred to the microcontroller by the
same pin DATAMSG (Rx) as reshaped bits. No data is stored or processed into the
chip. See Figure 1.
Note: In Rx mode, a clock recovery DATACLK is available on the digital interface to provide the
microcontroller with a synchronization signal.
Wake-up Mode The chip is set up in a special Rx mode called sleep mode. The chip wakes up periodi-
cally thanks to its internal timer (stand alone procedure, the microcontroller is in power-
down mode), waiting for an expected message previously defined. If no correct
sequence is received, the periodic scan continues.
If a correct message is detected, its data field is stored into the AT86RF211 (up to 32
bits) and an interrupt is generated on the WAKEUP pin.
See Figure 2 and Figure 3.