PIC18F2450 MICROCHIP [Microchip Technology], PIC18F2450 Datasheet - Page 193

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

REGISTER 18-1:
© 2006 Microchip Technology Inc.
bit 7
Legend:
R = Readable bit
-n = Value when device is unprogrammed
bit 7-6
bit 5
bit 4-3
bit 2-0
U-0
—
Unimplemented: Read as ‘0’
USBDIV: USB Clock Selection bit (used in Full-Speed USB mode only; UCFG:FSEN = 1)
1 = USB clock source comes from the 96 MHz PLL divided by 2
0 = USB clock source comes directly from the primary oscillator block with no postscale
CPUDIV1:CPUDIV0: System Clock Postscaler Selection bits
For XT, HS, EC and ECIO Oscillator modes:
11 = Primary oscillator divided by 4 to derive system clock
10 = Primary oscillator divided by 3 to derive system clock
01 = Primary oscillator divided by 2 to derive system clock
00 = Primary oscillator used directly for system clock (no postscaler)
For XTPLL, HSPLL, ECPLL and ECPIO Oscillator modes:
11 = 96 MHz PLL divided by 6 to derive system clock
10 = 96 MHz PLL divided by 4 to derive system clock
01 = 96 MHz PLL divided by 3 to derive system clock
00 = 96 MHz PLL divided by 2 to derive system clock
PLLDIV2:PLLDIV0: PLL Prescaler Selection bits
111 = Divide by 12 (48 MHz oscillator input)
110 = Divide by 10 (40 MHz oscillator input)
101 = Divide by 6 (24 MHz oscillator input)
100 = Divide by 5 (20 MHz oscillator input)
011 = Divide by 4 (16 MHz oscillator input)
010 = Divide by 3 (12 MHz oscillator input)
001 = Divide by 2 (8 MHz oscillator input)
000 = No prescale (4 MHz oscillator input drives PLL directly)
U-0
—
CONFIG1L: CONFIGURATION REGISTER 1 LOW (BYTE ADDRESS 300000h)
P = Programmable bit
USBDIV
R/P-0
Advance Information
CPUDIV1
R/P-0
U = Unimplemented bit, read as ‘0’
u = Unchanged from programmed state
CPUDIV0
R/P-0
PIC18F2450/4450
PLLDIV2
R/P-1
PLLDIV1
R/P-1
DS39760A-page 191
PLLDIV0
R/P-1
bit 0