Microchip Technology MA330031-2 Data Sheet
2011-2013 Microchip Technology Inc.
DS70000657H-page 123
dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/50X AND PIC24EPXXXGP/MC20X
6.0
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
• BOR: Brown-out Reset
• MCLR: Master Clear Pin Reset
• SWR: RESET Instruction
• WDTO: Watchdog Timer Time-out Reset
• CM: Configuration Mismatch Reset
• TRAPR: Trap Conflict Reset
• IOPUWR: Illegal Condition Device Reset
controls the device Master Reset Signal, SYSRST. The
following is a list of device Reset sources:
• POR: Power-on Reset
• BOR: Brown-out Reset
• MCLR: Master Clear Pin Reset
• SWR: RESET Instruction
• WDTO: Watchdog Timer Time-out Reset
• CM: Configuration Mismatch Reset
• TRAPR: Trap Conflict Reset
• IOPUWR: Illegal Condition Device Reset
- Illegal Opcode Reset
- Uninitialized W Register Reset
- Security Reset
- Uninitialized W Register Reset
- Security Reset
A simplified block diagram of the Reset module is
shown in
shown in
.
Any active source of Reset will make the SYSRST
signal active. On system Reset, some of the registers
associated with the CPU and peripherals are forced to
a known Reset state and some are unaffected.
signal active. On system Reset, some of the registers
associated with the CPU and peripherals are forced to
a known Reset state and some are unaffected.
All types of device Reset set a corresponding status bit
in the RCON register to indicate the type of Reset (see
in the RCON register to indicate the type of Reset (see
A POR clears all the bits, except for the POR and BOR
bits (RCON<1:0>), that are set. The user application
can 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 does
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 manual.
bits (RCON<1:0>), that are set. The user application
can 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 does
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 manual.
For all Resets, the default clock source is determined
by the FNOSC<2:0> bits in the FOSCSEL Configura-
tion register. The value of the FNOSC<2:0> bits is
loaded into NOSC<2:0> (OSCCON<10:8>) on Reset,
which in turn, initializes the system clock.
by the FNOSC<2:0> bits in the FOSCSEL Configura-
tion register. The value of the FNOSC<2:0> bits is
loaded into NOSC<2:0> (OSCCON<10:8>) on Reset,
which in turn, initializes the system clock.
FIGURE 6-1:
RESET SYSTEM BLOCK DIAGRAM
Note 1:
This data sheet summarizes the
features of the dsPIC33EPXXXGP50X,
dsPIC33EPXXXMC20X/50X and
PIC24EPXXXGP/MC20X families of
devices. It is not intended to be a
comprehensive reference source. To com-
plement the information in this data sheet,
refer to “Reset” (DS70602) in the
“dsPIC33/PIC24 Family Reference Man-
ual”
features of the dsPIC33EPXXXGP50X,
dsPIC33EPXXXMC20X/50X and
PIC24EPXXXGP/MC20X families of
devices. It is not intended to be a
comprehensive reference source. To com-
plement the information in this data sheet,
refer to “Reset” (DS70602) in the
“dsPIC33/PIC24 Family Reference Man-
ual”
, which is available from the Microchip
www.microchip.com
).
2:
Some registers and associated bits
described in this section may not be
available on all devices. Refer to
described in this section may not be
available on all devices. Refer to
in
this data sheet for device-specific register
and bit information.
and bit information.
Note:
Refer to the specific peripheral section or
of
this manual for register Reset states.
Note:
The status bits in the RCON register
should be cleared after they are read so
that the next RCON register value after a
device Reset is meaningful.
should be cleared after they are read so
that the next RCON register value after a
device Reset is meaningful.
MCLR
V
DD
BOR
Sleep or Idle
RESET
Instruction
WDT
Module
Glitch Filter
Trap Conflict
Illegal Opcode
Uninitialized W Register
SYSRST
V
DD
Rise
Detect
POR
Configuration Mismatch
Security Reset
Internal
Regulator