PIC18LF24K Datasheet, PDF (79/594 Pages) –

PIC18(L)F26/45/46K40
8.12 Start-up Sequence
Upon the release of a POR or BOR, the following must
occur before the device will begin executing:
1. Power-up Timer runs to completion (if enabled).
2. Oscillator start-up timer runs to completion (if
required for selected oscillator source).
3. MCLR must be released (if enabled).
FIGURE 8-4:
RESET START-UP SEQUENCE
The total time out will vary based on oscillator
configuration and Power-up Timer configuration. See
Section 4.0 “Oscillator Module (with Fail-Safe
Clock Monitor)” for more information.
The Power-up Timer and oscillator start-up timer run
independently of MCLR Reset. If MCLR is kept low
long enough, the Power-up Timer and oscillator
Start-up Timer will expire. Upon bringing MCLR high,
the device will begin execution after 10 FOSC cycles
(see Figure 8-4). This is useful for testing purposes or
to synchronize more than one device operating in
parallel.
VDD
Internal POR
Power-up Timer
MCLR
Internal RESET
Oscillator Modes
External Crystal
Oscillator Start-up Timer
Oscillator
FOSC
Internal Oscillator
Oscillator
FOSC
External Clock (EC)
CLKIN
FOSC
TPWRT
TMCLR
TOST
 2016 Microchip Technology Inc.
Preliminary
DS40001816C-page 79