
2001 Microchip Technology Inc.
Advance Information
DS39582A-page 147
PIC16F87XA
14.10 Power Control/Status Register
(PCON)
The Power Control/Status Register, PCON, has up to
two bits depending upon the device.
Bit0 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.
Bit1 is POR (Power-on Reset Status bit). It is cleared on
a Power-on Reset and unaffected otherwise. 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 CONDITION FOR SPECIAL REGISTERS
Oscillator Configuration
Power-up
Brown-out
Wake-up from
SLEEP
PWRTE = 0
PWRTE = 1
XT, HS, LP
RC
72 ms + 1024T
OSC
72 ms
1024T
OSC
—
72 ms + 1024T
OSC
72 ms
1024T
OSC
—
POR
BOR
TO
PD
0
x
1
1
Power-on Reset
Illegal, TO is set on POR
Illegal, PD is set on POR
Brown-out Reset
WDT Reset
WDT Wake-up
MCLR Reset during normal operation
MCLR Reset during SLEEP or interrupt wake-up from SLEEP
0
0
x
x
0
x
x
0
1
0
1
1
1
1
1
1
0
0
1
0
1
1
u
u
1
1
1
0
Legend:
x
= don’t care,
u
= unchanged
Condition
Program
Counter
STATUS
Register
PCON
Register
Power-on Reset
MCLR Reset during normal operation
MCLR Reset during SLEEP
WDT Reset
WDT Wake-up
Brown-out Reset
Interrupt wake-up from SLEEP
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).
000h
000h
000h
000h
PC + 1
000h
PC + 1
(1)
0001 1xxx
000u uuuu
---- --0x
---- --uu
0001 0uuu
---- --uu
0000 1uuu
uuu0 0uuu
---- --uu
---- --uu
0001 1uuu
---- --u0
uuu1 0uuu
---- --uu