Datasheet

PIC18F87K22 FAMILY
DS39960D-page 406  2009-2011 Microchip Technology Inc.
REGISTER 28-2: CONFIG1H: CONFIGURATION REGISTER 1 HIGH (BYTE ADDRESS 300001h)
R/P-0 R/P-0 U-0 U-0 R/P-1 R/P-0 R/P-0 R/P-0
IESO FCMEN
—PLLCFG
(1)
FOSC3
(2)
FOSC2
(2)
FOSC1
(2)
FOSC0
(2)
bit 7 bit 0
Legend: P = Programmable bit
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
bit 7
IESO: Internal/External Oscillator Switchover bit
1 = Two-Speed Start-up is enabled
0 = Two-Speed Start-up is disabled
bit 6
FCMEN: Fail-Safe Clock Monitor Enable bit
1 = Fail-Safe Clock Monitor is enabled
0 = Fail-Safe Clock Monitor is disabled
bit 5
Unimplemented: Read as ‘0’
bit 4
PLLCFG: 4x PLL Enable bit
(1)
1 = Oscillator is multiplied by 4
0 = Oscillator is used directly
bit 3-0
FOSC<3:0>: Oscillator Selection bits
(2)
1101 = EC1, EC oscillator (low power, DC-160 kHz)
1100
= EC1IO, EC oscillator with CLKOUT function on RA6 (low power, DC-160 kHz)
1011
= EC2, EC oscillator (medium power, 160 kHz-16 MHz)
1010
= EC2IO, EC oscillator with CLKOUT function on RA6 (medium power, DC-160 kHz-16 MHz)
1001
= INTIO1, internal RC oscillator with CLKOUT function on RA6
1000 = INTIO2, internal RC oscillator
0111 = RC, external RC oscillator
0110 = RCIO, external RC oscillator with CKLOUT function on RA6
0101 = EC3, EC oscillator (high power, 4 MHz-64 MHz)
0100
= EC3IO, EC oscillator with CLKOUT function on RA6 (high power, 4 MHz-64 MHz)
0011
= HS1, HS oscillator (medium power, 4 MHz-16 MHz)
0010
= HS2, HS oscillator (high power, 16 MHz-25 MHz)
0001
= XT oscillator
0000 = LP oscillator
Note 1: Not valid for the INTIOx PLL mode.
2: INTIO + PLL can be enabled only by the PLLEN bit (OSCTUNE<6>). Other PLL modes can be enabled by
either the PLLEN bit or the PLLCFG (CONFIG1H<4>) bit.