Microchip Technology MA240029 データシート

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 2010-2011 Microchip Technology Inc.
DS39996F-page 89
PIC24FJ128GA310 FAMILY
7.0
RESETS
The Reset module combines all Reset sources and
controls the device Master Reset Signal, SYSRST. The
following is a list of device Reset sources:
• POR: Power-on Reset 
• MCLR: Pin Reset
• SWR: RESET Instruction
• WDT: Watchdog Timer Reset
• BOR: Brown-out Reset
• CM: Configuration Mismatch Reset
• TRAPR: Trap Conflict Reset
• IOPUWR: Illegal Opcode Reset
• UWR: Uninitialized W Register Reset
A simplified block diagram of the Reset module is
shown in 
.
Any active source of Reset will make the SYSRST
signal active. Many registers associated with the CPU
and peripherals are forced to a known Reset state.
Most registers are unaffected by a Reset; their status is
unknown on POR and unchanged by all other Resets.
All types of device Reset will set a corresponding status
bit in the RCON register to indicate the type of Reset
(see 
). In addition, Reset events occurring
while an extreme power-saving feature is in use (such
as V
BAT
) will set one or more status bits in the RCON2
register (
). A POR will clear all bits, except
for the BOR and POR (RCON<1:0>) bits, which are
set. The user may set or clear any bit at any time during
code execution. The RCON bits only serve as status
bits. Setting a particular Reset status bit in software will
not cause a device Reset to occur.
The RCON register also has other bits associated with
the Watchdog Timer and device power-saving states.
The function of these bits is discussed in other sections
of this data sheet. 
FIGURE 7-1:
RESET SYSTEM BLOCK DIAGRAM
Note:
This data sheet summarizes the features of
this group of PIC24F devices. It is not
intended to be a comprehensive reference
source. For more information, refer to the
PIC24F Family Reference Manual”,
Section 7. “Reset”
 (DS39712). The infor-
mation in this data sheet supersedes the
information in the FRM.
Note:
Refer to the specific peripheral or CPU
section of this manual for register Reset
states.
Note:
The status bits in the RCON registers
should be cleared after they are read so
that the next RCON register values after a
device Reset will be meaningful. 
MCLR
V
DD
V
DD
 Rise
Detect
POR
Sleep or Idle
Brown-out
Reset
Enable Voltage Regulator
RESET
Instruction
WDT
Module
Glitch Filter
BOR
Trap Conflict
Illegal Opcode
Uninitialized W Register
SYSRST
Configuration Mismatch