PIC18F2420 MICROCHIP [Microchip Technology], PIC18F2420 Datasheet - Page 42

• Manufacturer Part Number: PIC18F2420
• Description: 28/40/44-Pin Enhanced Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2420/2520/4420/4520
3.5.4
Certain exits from power managed modes do not
invoke the OST at all. There are two cases:
• PRI_IDLE mode, where the primary clock source
• the primary clock source is not any of the LP, XT,
TABLE 3-2:
DS39631A-page 40
Note 1:
is not stopped and
HS or HSPLL modes.
Primary Device Clock
T1OSC or INTRC
2:
3:
4:
(PRI_IDLE mode)
before Wake-up
Clock Source
(Sleep mode)
INTOSC
T
with any other required delays (see Section 3.4 “Idle Modes”). On Reset, INTOSC defaults to 1 MHz.
Includes both the INTOSC 8 MHz source and postscaler derived frequencies.
T
also designated as T
Execution continues during T
EXIT WITHOUT AN OSCILLATOR
START-UP DELAY
CSD
OST
None
(parameter 38) is a required delay when waking from Sleep and all Idle modes and runs concurrently
is the Oscillator Start-up Timer (parameter 32). t
EXIT DELAY ON WAKE-UP BY RESET FROM SLEEP MODE OR ANY IDLE MODE
(BY CLOCK SOURCES)
(2)
(1)
PLL
.
IOBST
after Wake-up
Clock Source
LP, XT, HS
INTOSC
LP, XT, HS
INTOSC
LP, XT, HS
INTOSC
LP, XT, HS
INTOSC
EC, RC
EC, RC
EC, RC
EC, RC
HSPLL
HSPLL
HSPLL
HSPLL
(parameter 39), the INTOSC stabilization period.
(2)
(1)
(1)
(1)
In these instances, the primary clock source either
does not require an oscillator start-up delay since it is
already running (PRI_IDLE), or normally does not
require an oscillator start-up delay (RC, EC and INTIO
Oscillator modes). However, a fixed delay of interval
T
leaving Sleep and Idle modes to allow the CPU to
prepare for execution. Instruction execution resumes
on the first clock cycle following this delay.
CSD
rc
is the PLL Lock-out Timer (parameter F12); it is
following the wake event is still required when
T
T
T
Exit Delay
OST
OST
OST
T
T
T
T
T
T
T
T
T
IOBST (4)
IOBST
None
CSD (1)
CSD
CSD
CSD
OST
OST (4)
OST (3)
+ t
+ t
+ t
(3)
(1)
(1)
(1)
rc
rc
rc
(4)
(3)
(3)
(3)
 2004 Microchip Technology Inc.
Clock Ready Status
Bit (OSCCON)
OSTS
OSTS
OSTS
OSTS
IOFS
IOFS
IOFS
IOFS