DSPIC30F4013 Microchip Technology Inc., DSPIC30F4013 Datasheet - Page 147

• Manufacturer Part Number: DSPIC30F4013
• Description: Dspic30f3014/4013 High-performance, 16-bit Digital Signal Controllers
• Manufacturer: Microchip Technology Inc.

20.4
The PIC18F1220/1320 differentiates between various
kinds of Reset:
a)
b)
c)
d)
e)
f)
g)
h)
FIGURE 20-2:
20.4.1
A power-on event generates an internal POR pulse
when a V
the POR circuit threshold voltage (V
inally 1.85V. The device supply voltage characteristics
must meet specified starting voltage and rise rate
requirements. The POR pulse resets a POR timer and
places the device in the Reset state. The POR also
selects the device clock source identified by the
oscillator configuration fuses.
© 2007 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
RESET
POR: POWER-ON RESET
rise is detected. The Reset pulse occurs at
Trap Conflict
Illegal Opcode/
Uninitialized W Register
Brown-out
V
Sleep or Idle
Module
Detect
DD
WDT
Reset
RESET SYSTEM BLOCK DIAGRAM
Rise
BOREN
Glitch Filter
Digital
POR
POR
) which is nom-
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 20-5. 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 20-2.
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 μs and ensures that the device bias
circuits 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 is negated on the next leading
edge of the Q1 clock and the PC jumps to the Reset
vector.
The timing for the SYSRST signal is shown in
Figure 20-3 through Figure 20-5.
dsPIC30F3014/4013
PWRT
) is applied. The T
POR
S
R
+ T
PWRT
Q
. When these delays
DS70138E-page 145
PWRT
SYSRST
POR
parameter
, which is