PIC18F44J50-I Datasheet, PDF (63/562 Pages) Microchip Technology – 28/44-Pin, Low-Power, High-Performance USB Microcontrollers

PIC18F46J50 FAMILY
5.0 RESET
The PIC18F46J50 family of devices differentiate
among various kinds of Reset:
a) Power-on Reset (POR)
b) MCLR Reset during normal operation
c) MCLR Reset during power-managed modes
d) Watchdog Timer (WDT) Reset (during
execution)
e) Configuration Mismatch (CM)
f) Brown-out Reset (BOR)
g) RESET Instruction
h) Stack Full Reset
i) Stack Underflow Reset
j) Deep Sleep Reset
This section discusses Resets generated by MCLR,
POR and BOR, and covers the operation of the various
start-up timers.
For information on WDT Resets, see Section 27.2
“Watchdog Timer (WDT)”. For Stack Reset events,
see Section 6.1.4.4 “Stack Full and Underflow
Resets” and for Deep Sleep mode, see Section 4.6
“Deep Sleep Mode”.
Figure 5-1 provides a simplified block diagram of the
on-chip Reset circuit.
5.1 RCON Register
Device Reset events are tracked through the RCON
register (Register 5-1). The lower five bits of the register
indicate that a specific Reset event has occurred. In
most cases, these bits can only be set by the event and
must be cleared by the application after the event. The
state of these flag bits, taken together, can be read to
indicate the type of Reset that just occurred. This is
described in more detail in Section 5.7 “Reset State of
Registers”.
FIGURE 5-1:
SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
RESET Instruction
Configuration Word Mismatch
Stack
Pointer
Stack Full/Underflow Reset
External Reset
MCLR
( )_IDLE
Deep Sleep Reset
Sleep
VDD
VDDCORE
WDT
Time-out
VDD Rise
Detect
POR Pulse
Brown-out
Reset⁽¹⁾
PWRT
INTRC
Brown-out
Reset⁽²⁾
PWRT
F: 5-Bit Ripple Counter
LF: 11-Bit Ripple Counter
S
Chip_Reset
R
Q
Note 1:
2:
The VDD monitoring BOR circuit can be enabled or disabled on “LF” devices based on the DSBOREN
(CONFIG3L<2>) Configuration bit. On “F” devices, the VDD monitoring BOR circuit is only enabled during Deep
Sleep mode by DSBOREN (CONFIG3L<2>).
The VDDCORE monitoring BOR circuit is only implemented on “F” devices. It is always used, except while in Deep
Sleep mode. The VDDCORE monitoring BOR circuit has a trip point threshold of VBOR (Parameter D005).
 2011 Microchip Technology Inc.
DS39931D-page 63