2003 Microchip Technology Inc.
DS39582B-page 149
PIC16F87XA
14.10 Power Control/Status Register
(PCON)
The Power Control/Status Register, PCON, has up to
two bits depending upon the device.
Bit 0 is the Brown-out Reset Status bit, BOR. The BOR
bit is unknown on a Power-on Reset. It must then be set
by the user and checked on subsequent Resets to see if
it has been cleared, indicating that a BOR has occurred.
When the Brown-out Reset is disabled, the state of the
BOR bit is unpredictable and is, therefore, not valid at
any time.
Bit 1 is the Power-on Reset Status bit, POR. It is
cleared on a Power-on Reset and unaffected other-
wise. The user must set this bit following a Power-on
Reset.
TABLE 14-3:
TIME-OUT IN VARIOUS SITUATIONS
TABLE 14-4:
STATUS BITS AND THEIR SIGNIFICANCE
TABLE 14-5:
RESET CONDITIONS FOR SPECIAL REGISTERS
Oscillator Configuration
Power-up
Brown-out
Wake-up from
Sleep
PWRTE =
0
PWRTE =
1
XT, HS, LP
72 ms + 1024 T
OSC
1024 T
OSC
72 ms + 1024 T
OSC
1024 T
OSC
RC
72 ms
—
72 ms
—
POR
BOR
TO
PD
Condition
0
x
1
1
Power-on Reset
0
x
0
x
Illegal, TO is set on POR
0
x
x
0
Illegal, PD is set on POR
1
0
1
1
Brown-out Reset
1
1
0
1
WDT Reset
1
1
0
0
WDT Wake-up
1
1
u
u
MCLR Reset during normal operation
1
1
1
0
MCLR Reset during Sleep or Interrupt Wake-up from Sleep
Legend:
x
= don’t care,
u
= unchanged
Condition
Program
Counter
Status
Register
PCON
Register
Power-on Reset
000h
0001 1xxx
---- --0x
MCLR Reset during normal operation
000h
000u uuuu
---- --uu
MCLR Reset during Sleep
000h
0001 0uuu
---- --uu
WDT Reset
000h
0000 1uuu
---- --uu
WDT Wake-up
PC + 1
uuu0 0uuu
---- --uu
Brown-out Reset
000h
0001 1uuu
---- --u0
Interrupt Wake-up from Sleep
PC + 1
(1)
uuu1 0uuu
---- --uu
Legend:
u
= unchanged,
x
= unknown,
-
= unimplemented bit, read as ‘
0
’
Note 1:
When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector
(0004h).
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