CC1110Fx / CC1111Fx
13.1.2 Active Mode and Power Modes
This power mode is used to achieve the
operating mode with the lowest power
consumption. In PM3 all internal circuits that
are powered from internal voltage regulators
are turned off.
The different operating modes are described in
detail in the five following sections.
13.1.2.1 Active Mode
Reset (POR, or external) and external I/O port
interrupts are the only functions that are
operating in this mode. I/O pins retain the I/O
mode and output value set before entering
PM3. A reset or external interrupt condition will
wake the device and make it enter active
mode. The content of RAM and registers is
preserved in this mode. PM3 uses the same
power down/up sequence as PM2.
This is the full functional mode of operation
where the CPU, peripherals, and RF
transceiver are active. The voltage regulator to
the digital core is on and either the high speed
RC oscillator or the high speed crystal
oscillator or both are running together with
either the Low power RC oscillator or the
32.768 kHz crystal oscillator.
PM3 is used to achieve ultra low power
consumption when waiting for an external
event.
13.1.2.2 PM0
If the PCON.IDLE bit is set to 1 while in active
mode, the CPU will be idle (clock gated) until
any interrupt occur. All other peripherals will
function as normal while the CPU is halted.
When entering active mode from PM1, PM2, or
PM3, the high-speed oscillators, which where
running when entering PM{1_3}, are started. If
the high speed crystal oscillator is selected as
source for the system clock (CLKCON.OSC=0),
the system clock will use the HS RCOSC as
clock source until the high speed crystal
oscillator is stable (SLEEP.XOSC_STB=1).
13.1.2.3 PM1
In PM1, the high speed oscillators (high speed
XOSC and HS RCOSC) are powered down
thereby halting the CPU and peripherals. The
digital voltage regulator, the power-on reset,
external interrupts, the low power RC oscillator
or the 32.768 kHz crystal oscillator and Sleep
Timer peripherals are active. I/O pins retain the
I/O mode and output value set before entering
PM1. When PM1 is entered, a power down
sequence is run.
13.1.3 Power Management Control
The required power mode is selected by the
SLEEP.MODE setting. Setting the IDLE bit in
the PCON SFR after setting the MODE bits,
makes the CC1111Fx/CC1111Fx enter the selected
power mode. The following procedure must be
followed to be able to safely put the device into
one of the power modes PM{1-3}:
PM1 is used when the expected time until a
wakeup event is relatively short since PM1
uses a fast power down/up sequence.
// Pseudo Code
SLEEP.MODE = PM{1-3}
NOP();
13.1.2.4 PM2
PM2 has the second lowest power
consumption. In PM2, the power-on reset,
external interrupts, the low power RC oscillator
or the 32.768 kHz crystal oscillator and Sleep
Timer peripherals are active. I/O pins retain the
I/O mode and output value set before entering
PM2. The content of RAM and most registers
is preserved in this mode (see Table 31, Table
32, and Table 33). All other internal circuits are
powered down. When PM2 is entered, a power
down sequence is run.
NOP();
NOP();
If (SLEEP_MODE != 0)
PCON.IDLE = 1;
An interrupt from port pins or Sleep Timer (not
PM3), or a power-on reset will wake the device
and bring it into active mode. Since an
interrupt can occur before the device has
actually entered PM{1-3}, it is necessary to
clear the MODE bits before returning from all
ISRs associated with interrupts that can be
used to wake the device from PM{1-3}. It
should be noted that all port interrupts and
Sleep Timer interrupt are blocked when
SLEEP.MODEis different from 00, thus the time
PM2 is typically entered when using the Sleep
Timer as the wakeup event. Please see
section 13.8.1 for minimum sleep time when
using the Sleep Timer.
13.1.2.5 PM3
In PM3 the internal voltage regulator and all
oscillators are turned off.
between setting SLEEP.MODE
≠
0 and
asserting PCON.IDLE should be as short as
SWRS033E
Page 78 of 239
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