
2004 Microchip Technology Inc.
DS30491C-page 347
PIC18F6585/8585/6680/8680
REGISTER 24-1:
CONFIG1H: CONFIGURATION REGISTER 1 HIGH (BYTE ADDRESS 300001h)
U-0
R/P-1
U-0
R/P-1
—
OSCSEN
—
FOSC3
FOSC2
FOSC1
FOSC0
bit 7
bit 0
bit 7-6
Unimplemented: Read as ‘0’
bit 5
OSCSEN: Oscillator System Clock Switch Enable bit
1
= Oscillator system clock switch option is disabled (main oscillator is source)
0
= Timer1 oscillator system clock switch option is enabled (oscillator switching is enabled)
bit 4
Unimplemented: Read as ‘0’
bit 3-0
FOSC3:FOSC0: Oscillator Selection bits
1111
= RC oscillator with OSC2 configured as RA6
1110
= HS oscillator with SW enabled 4x PLL
1101
= EC oscillator with OSC2 configured as RA6 and SW enabled 4x PLL
1100
= EC oscillator with OSC2 configured as RA6 and HW enabled 4x PLL
1011
= Reserved; do not use
1010
= Reserved; do not use
1001
= Reserved; do not use
1000
= Reserved; do not use
0111
= RC oscillator with OSC2 configured as RA6
0110
= HS oscillator with HW enabled 4x PLL
0101
= EC oscillator with OSC2 configured as RA6
0100
= EC oscillator with OSC2 configured as divide by 4 clock output
0011
= RC oscillator with OSC2 configured as divide by 4 clock output
0010
= HS oscillator
0001
= XT oscillator
0000
= LP oscillator
Legend:
R = Readable bit
P = Programmable bit
U = Unimplemented bit, read as ‘0’
- n = Value when device is unprogrammed
u = Unchanged from programmed state