
2002 Microchip Technology Inc.
DS41120B-page 21
PIC16C717/770/771
2.2.2.8
PCON REGISTER
The Power Control (PCON) register contains a flag bit
to allow differentiation between a Power-on Reset
(POR) to an external MCLR Reset or WDT Reset.
Those devices with brown-out detection circuitry con-
tain an additional bit to differentiate a Brown-out Reset
condition from a Power-on Reset condition.
The PCON register also contains the frequency select
bit of the INTRC or ER oscillator.
REGISTER 2-8:
POWER CONTROL REGISTER (PCON: 8Eh)
Note:
BOR is unknown on Power-on Reset. It
must then be set by the user and checked
on subsequent RESETS to see if BOR is
clear, indicating a brown-out has occurred.
The BOR status bit is a don’t care and is
not necessarily predictable if the brown-out
circuit is disabled (by clearing the BODEN
bit in the Configuration word).
U-0
R/W-1
U-0
R/W-q
—
OSCF
—
POR
BOR
bit 7
bit 0
bit 7-4
Unimplemented: Read as '0'
bit 3
OSCF: Oscillator Speed bit
INTRC Mode
1
= 4 MHz nominal
0
= 37 kHz nominal
ER Mode
1
= Oscillator frequency depends on the external resistor value on the OSC1 pin.
0
= 37 kHz nominal
All other modes
x
= Ignored
bit 2
Unimplemented: Read as '0'
bit 1
POR: Power-on Reset Status bit
1
= No Power-on Reset occurred
0
= A Power-on Reset occurred (must be set in software after a Power-on Reset occurs)
bit 0
1
= No Brown-out Reset occurred
0
= A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs)
Legend:
q = Value depends on conditions
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
’1’ = Bit is set
’0’ = Bit is cleared
x = Bit is unknown