PIC16C770 Microchip Technology Inc., PIC16C770 Datasheet - Page 23

• Manufacturer Part Number: PIC16C770
• Description: 18/20-pin, 8-bit Cmos Microcontrollers With 10/12-bit A/d
• Manufacturer: Microchip Technology Inc.

2.2.2.8
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:
2002 Microchip Technology Inc.
bit 7-4
bit 3
bit 2
bit 1
bit 0
PCON REGISTER
POWER CONTROL REGISTER (PCON: 8Eh)
Unimplemented: Read as '0'
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
Unimplemented: Read as '0'
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)
BOR: Brown-out Reset Status bit (See Section 2.2.2.8 Note)
1 = No Brown-out Reset occurred
0 = A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs)
bit 7
Legend:
R = Readable bit
- n = Value at POR
U-0
—
U-0
—
U-0
—
W = Writable bit
’1’ = Bit is set
U-0
—
Note:
PIC16C717/770/771
R/W-1
OSCF
q = Value depends on conditions
U = Unimplemented bit, read as ‘0’
’0’ = Bit is cleared
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
—
x = Bit is unknown
R/W-q
POR
DS41120B-page 21
R/W-q
BOR
bit 0