PIC18F2450 MICROCHIP [Microchip Technology], PIC18F2450 Datasheet - Page 194

• Manufacturer Part Number: PIC18F2450
• Description: 28/40/44-Pin, High-Performance, 12 MIPS, Enhanced Flash, USB Microcontrollers with nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2450/4450
REGISTER 18-2:
DS39760A-page 192
bit 7
Legend:
R = Readable bit
-n = Value when device is unprogrammed
bit 7
bit 6
bit 5-4
bit 3-0
Note 1:
R/P-0
IESO
The microcontroller and USB module both use the selected oscillator as their clock source in XT, HS and
EC modes. The USB module uses the indicated XT, HS or EC oscillator as its clock source whenever the
microcontroller uses the internal oscillator.
IESO: Internal/External Oscillator Switchover bit
1 = Oscillator Switchover mode enabled
0 = Oscillator Switchover mode disabled
FCMEN: Fail-Safe Clock Monitor Enable bit
1 = Fail-Safe Clock Monitor enabled
0 = Fail-Safe Clock Monitor disabled
Unimplemented: Read as ‘0’
FOSC3:FOSC0: Oscillator Selection bits
111x = HS oscillator, PLL enabled (HSPLL)
110x = HS oscillator (HS)
1011 = Internal oscillator, HS oscillator used by USB (INTHS)
1010 = Internal oscillator, XT used by USB (INTXT)
1001 = Internal oscillator, CLKO function on RA6, EC used by USB (INTCKO)
1000 = Internal oscillator, port function on RA6, EC used by USB (INTIO)
0111 = EC oscillator, PLL enabled, CLKO function on RA6 (ECPLL)
0110 = EC oscillator, PLL enabled, port function on RA6 (ECPIO)
0101 = EC oscillator, CLKO function on RA6 (EC)
0100 = EC oscillator, port function on RA6 (ECIO)
001x = XT oscillator, PLL enabled (XTPLL)
000x = XT oscillator (XT)
FCMEN
R/P-0
CONFIG1H: CONFIGURATION REGISTER 1 HIGH (BYTE ADDRESS 300001h)
P = Programmable bit
U-0
—
Advance Information
U-0
—
(1)
u = Unchanged from programmed state
U = Unimplemented bit, read as ‘0’
FOSC3
R/P-0
(1)
FOSC2
R/P-1
(1)
© 2006 Microchip Technology Inc.
FOSC1
R/P-1
(1)
FOSC0
R/P-1
bit 0
(1)