DSPIC30F2012 Microchip Technology Inc., DSPIC30F2012 Datasheet - Page 127

• Manufacturer Part Number: DSPIC30F2012
• Description: Dspic30f2011/2012/3012/3013 High-performance Digital Signal Controllers
• Manufacturer: Microchip Technology Inc.

17.3
The PIC18F1220/1320 differentiates between various
kinds of Reset:
a)
b)
c)
d)
e)
f)
g)
h)
FIGURE 17-2:
17.3.1
A power-on event will generate an internal POR pulse
when a V
at the POR circuit threshold voltage (V
nominally 1.85V. The device supply voltage character-
istics must meet specified starting voltage and rise rate
requirements. The POR pulse will reset a POR timer
and place the device in the Reset state. The POR also
selects the device clock source identified by the
oscillator configuration fuses.
© 2006 Microchip Technology Inc.
Power-on Reset (POR)
MCLR Reset during normal operation
MCLR Reset during Sleep
Watchdog Timer (WDT) Reset (during normal
operation)
Programmable Brown-out Reset (BOR)
RESET Instruction
Reset caused by trap lockup (TRAPR)
Reset caused by illegal opcode or by using an
uninitialized W register as an address pointer
(IOPUWR)
MCLR
V
DD
Reset
DD
Instruction
POR: POWER-ON RESET
RESET
rise is detected. The Reset pulse will occur
Trap Conflict
Illegal Opcode/
Uninitialized W Register
Brown-out
V
Sleep or Idle
Module
DD
Detect
WDT
Reset
RESET SYSTEM BLOCK DIAGRAM
Rise
BOREN
Glitch Filter
Digital
POR
dsPIC30F2011/2012/3012/3013
POR
) which is
BOR
Different registers are affected in different ways by var-
ious Reset conditions. Most registers are not affected
by a WDT wake-up since this is viewed as the resump-
tion of normal operation. Status bits from the RCON
register are set or cleared differently in different Reset
situations, as indicated in Table 17-5. These bits are
used in software to determine the nature of the Reset.
A block diagram of the On-Chip Reset Circuit is shown
in Figure 17-2.
A MCLR noise filter is provided in the MCLR Reset
path. The filter detects and ignores small pulses.
Internally generated Resets do not drive MCLR pin low.
The POR circuit inserts a small delay, T
nominally 10 s and ensures that the device bias cir-
cuits are stable. Furthermore, a user selected power-
up time-out (T
is based on device Configuration bits and can be 0 ms
(no delay), 4 ms, 16 ms or 64 ms. The total delay is at
device power-up, T
have expired, SYSRST will be negated on the next
leading edge of the Q1 clock and the PC will jump to the
Reset vector.
The timing for the SYSRST signal is shown in
Figure 17-3 through Figure 17-5.
PWRT
) is applied. The T
POR
S
R
+ T
PWRT
Q
. When these delays
DS70139E-page 125
PWRT
POR
SYSRST
parameter
, which is