Datasheet

 1998-2013 Microchip Technology Inc. DS40182D-page 55
PIC16CE62X
10.4.5 TIME-OUT SEQUENCE
On power-up, the time-out sequence is as follows: First
PWRT time-out is invoked after POR has expired, then
OST is activated. The total time-out will vary based on
oscillator configuration and P
WRTE bit status. For
example, in RC mode with PW
RTE bit erased (PWRT
disabled), there will be no time-out at all. Figure 10-8,
Figure 10-9 and Figure 10-10 depict time-out
sequences.
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, the time-outs will expire. Then
bringing MCLR
high will begin execution immediately
(see Figure 10-9). This is useful for testing purposes or
to synchronize more than one PIC
®
device operating in
parallel.
Table 10-5 shows the reset conditions for some special
registers, while Table 10-6 shows the reset conditions
for all the registers.
10.4.6 POWER CONTROL (PCON)/STATUS
REGISTER
The power control/status register, PCON (address
8Eh) has two bits.
Bit0 is BO
R (Brown-out). BOR is unknown on
power-on-reset. It must then be set by the user and
checked on subsequent resets to see if BOR = 0
indicating that a brown-out has occurred. The BO
R
status bit is a don’t care and is not necessarily
predictable if the brown-out circuit is disabled (by
setting BODEN bit = 0 in the Configuration word).
Bit1 is POR
(Power-on-reset). It is a ‘0’ on
power-on-reset and unaffected otherwise. The user
must write a ‘1’ to this bit following a power-on-reset.
On a subsequent reset, if POR
is ‘0’, it will indicate that
a power-on-reset must have occurred (V
DD may have
gone too low).
TABLE 10-3: TIME-OUT IN VARIOUS SITUATIONS
TABLE 10-4: STATUS/PCON BITS AND THEIR SIGNIFICANCE
Legend: x = unknown, u = unchanged
Oscillator Configuration
Power-up
Brown-out Reset
Wake-up
from SLEEP
PWRTE
= 0 PWRTE = 1
XT, HS, LP 72 ms + 1024 TOSC 1024 TOSC 72 ms + 1024 TOSC 1024 TOSC
RC 72 ms — 72 ms —
POR
BOR TO PD
0X11Power-on-reset
0X0XIllegal, TO
is set on POR
0XX0Illegal, PD is set on POR
10XXBrown-out Reset
110uWDT Reset
1100WDT Wake-up
11uuMCLR
reset during normal operation
1110MCLR
reset during SLEEP