2 basic operating mode description, 1 sleep - sleep state, 2 trx_off - clock state – Rainbow Electronics ATmega128RFA1 User Manual
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8266A-MCU Wireless-12/09
ATmega128RFA1
Bit SLPTR is a multifunctional bit (refer to section
"Transceiver Pin Register TRXPR" on
for more details). Dependent on the radio transceiver state, a “0” to “1”
transition on SLPTR causes the following state transitions:
•
TRX_OFF
SLEEP
•
PLL_ON
BUSY_TX
Whereas resetting bit SLPTR to “0” causes the following state transitions:
•
SLEEP
TRX_OFF
Bit TRXRST causes a reset of all radio transceiver registers and forces the radio
transceiver into TRX_OFF state.
For all states except SLEEP, the state change commands FORCE_TRX_OFF or
TRX_OFF lead to a transition into TRX_OFF state. If the radio transceiver is in active
receive or transmit states (BUSY_*), the command FORCE_TRX_OFF interrupts these
active processes, and forces an immediate transition to TRX_OFF. In contrast a
TRX_OFF command is stored until an active state (receiving or transmitting) has been
finished. After that the transition to TRX_OFF is performed.
For a fast transition from receive or active transmit states to PLL_ON state the
command FORCE_PLL_ON is provided. In contrast to FORCE_TRX_OFF this
command does not disable the PLL and the analog voltage regulator AVREG. It is not
available in states SLEEP, and RESET.
The completion of each requested state-change shall always be confirmed by reading
the bits TRX_STATUS of register TRX_STATUS.
9.4.1.2 Basic Operating Mode Description
9.4.1.2.1 SLEEP – Sleep State
In radio transceiver SLEEP state, the entire radio transceiver is disabled. No circuitry is
operating. The radio transceiver’s current consumption is reduced to leakage current
only. This state can only be entered from state TRX_OFF, by setting the bit
SLPTR = “1”.
Setting SLPTR = “0” returns the radio transceiver to the TRX_OFF state. During radio
transceiver SLEEP the register contents remains valid while the content of the Frame
Buffer and the security engine (AES) are cleared.
TRXRST = “1” in SLEEP state returns the radio transceiver to TRX_OFF state and
thereby sets all registers to their reset values.
9.4.1.2.2 TRX_OFF – Clock State
This state is reached immediately after Power On or Reset. In TRX_OFF the crystal
oscillator is running. The digital voltage regulator is enabled, thus the radio transceiver
registers, the Frame Buffer and security engine (AES) are accessible (see section
"Security Module (AES)" on page 92
).
SLPTR and TRXRST in register TRXPR can be used for state control (see
for details). The analog front-end is disabled during TRX_OFF.
Entering the TRX_OFF state from radio transceiver SLEEP, or RESET state is
indicated by the TRX24_AWAKE interrupt.