CC2510FX Datasheet, PDF (141/253 Pages) List of Unclassifed Manufacturers – True System-on-Chip with Low Power RF Transceiver and 8051 MCU

CC2510Fx / CC2511Fx
register. Setting the SFR register
PCON.IDLE bit after setting the MODE bits,
enters the selected power mode.
An interrupt from port pins, or sleep timer
(not PM3) or a power-on reset will wake
the device and bring it into PM0 by
resetting the MODE bits.
13.10.3 System Clock
The system clock is derived from the
selected main clock source, which is the
high-speed (26/48 MHz) crystal oscillator
or the high-speed (13 MHz) RC oscillator.
The CLKCON.OSC bit selects the source of
the main system clock. Note that to use
the RF transceiver the high speed crystal
oscillator must be selected and stable.
When the SLEEP.XOSC_STB is 1, the
26/48 MHz crystal oscillator is stable and
can be used as the source for the system
clock.
The oscillator not selected as the system
clock source, will be set in power-down
mode by setting SLEEP.OSC_PD to 1.
Thus the high-speed RC oscillator may be
turned off when the 26/48 MHz crystal
oscillator has been selected as system
clock source and vice versa. When
SLEEP.OSC_PD is 0, both oscillators are
powered up and running.
The selected main clock source can be
divided down by setting the
CLKCON.CLKSPD register appropriately.
Eight different system clock frequencies
from 0.203 to 26 MHz for CC2510Fx or from
0.1875 to 24 MHz for CC2511Fx can be
used.
13.10.4 High-speed oscillators
Two high speed oscillators are present in
the device. The high-speed crystal
oscillator startup time may be too long for
some applications, therefore the device
will run on the high-speed RC oscillator
until crystal oscillator is stable. The high-
speed RC oscillator consumes less power
than the crystal oscillator, but since it is
not as accurate as the crystal oscillator it
can not be used for RF transceiver
operation.
13.10.5 32.768/34 kHz oscillators
Two low power oscillators are present in
the device. By default the low power RC
oscillator is enabled (see Table 12 on
page 16). The low power RC oscillator
consumes less power, but is less accurate
than the 32.768 kHz crystal oscillator.
When the high speed crystal oscillator is
running the low power RC oscillator is
continuously calibrated. It is calibrated to a
frequency equal to high speed crystal
frequency divided by 750. E.g. 34.67 kHz
with 26 MHz crystal (CC2510Fx) and 32 kHz
with 24 MHz crystal (CC2511Fx).
13.10.6 Timer Tick generation
The power management controller
generates a tick or enable signal for the
peripheral timers, thus acting as a
prescaler for the timers. This is a global
clock division for Timer 1, Timer 3 and
Timer 4. The tick speed is programmed
from 0.203 to 26 MHz for CC2510Fx or from
0.1875 to 24 MHz for CC2511Fx by setting
the
CLKCON.TICKSPD
register
appropriately.
Note: The CLKCON.TICKSPD register
cannot be set higher than
CLKCON.CLKSPD.
13.10.7 Data Retention
In power modes PM2 and PM3 parts of
SRAM will retain its contents. The content
of internal registers is also retained in
PM2/3.
The XDATA memory locations 0xF000-
0xFFFF (4096 bytes) retains data in
PM2/3. Please note one exception as
given below.
The XDATA memory locations 0xFDA2-
0xFEFF (350 bytes) will lose all data when
PM2/3 is entered. These locations will
contain undefined data when PM0 is re-
entered.
The registers which retain their contents
are the CPU registers, peripheral registers
and RF registers, therefore switching to
the low-power modes PM2/3 appears
transparent to software.
13.10.8 I/O and Radio
I/O port pins P1_0 and P1_1 do not have
internal pull-up/pull-down resistors. These
CC2510Fx/CC2511Fx PRELIMINARY Data Sheet (Rev. 1.2) SWRS055A Page 141 of
252