Modes Of Operation; Clocking Scheme - Nokia 6500 SLIDE RM-240 Service Manual

Power down can be initiated by pressing the power key again (the system is powered down with the aid of
SW). The power key is connected to EM ASIC N2200 (AVILMA) via PWRONX signal.

Modes of operation

Mode
NO_SUPPLY (dead) mode means that the main battery is not present or its voltage is too low (below
N2200 AVILMA master reset threshold) and that the back-up battery voltage is too low.
BACK_UP The main battery is not present or its voltage is too low but back-up battery voltage is
adequate and the 32 kHz oscillator is running (RTC is on).
PWR_OFF In this mode (warm), the main battery is present and its voltage is over N2300 BETTY
master reset threshold. All regulators are disabled, PurX is on low state, the RTC is on
and the oscillator is on. PWR_OFF (cold) mode is almost the same as PWR_OFF (warm),
but the RTC and the oscillator are off.
RESET RESET mode is a synonym for start-up sequence. RESET mode uses 32 kHz clock to count
the REST mode delay (typically 16ms).
SLEEP SLEEP mode is entered only from PWR_ON mode with the aid of SW when the system's
activity is low.
FLASHING FLASHING mode is for SW downloading.

Clocking scheme

In BB5.0, two main clocks are provided to the system: 38.4MHz RF clock produced by VCTCXO in RF section
and 32.768kHz sleep clock produced by EM ASIC N2200 with an external crystal.
32 k Sleep Clock is always powered on after startup. Sleep clock is used by RAP for low-power operation.
SMPS Clk is 2.4 MHz clock line from RAP to EM ASIC N2300. In deep sleep mode, when VCTCXO is off, this signal
is set to '0'-state.
BT Clk is 38.4 MHz signal from Ahneus ASIC to BT module.
CLK600. The clock source is an internal RC oscillator in EM ASIC N2300 (during the power-up sequence) or
RAPIDO SMPS Clk.
Sys Clk. The Sys Clock is used for the camera hardware accelerator (HWA, N3400).
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Description
RM-240
System Module
Issue 1