PIC18(L)F2X/4XK22
REGISTER 24-1: CONFIG1H: CONFIGURATION REGISTER 1 HIGH
R/P-0
IESO
bit 7
R/P-0
FCMEN
R/P-1
PRICLKEN
R/P-0
PLLCFG
R/P-0
R/P-1
R/P-0
FOSC<3:0>
R/P-1
bit 0
Legend:
R = Readable bit
P = Programmable bit
-n = Value when device is unprogrammed
U = Unimplemented bit, read as ‘0’
x = Bit is unknown
bit 7
bit 6
bit 5
bit 4
bit 3-0
Note 1:
IESO(1): Internal/External Oscillator Switchover bit
1 = Oscillator Switchover mode enabled
0 = Oscillator Switchover mode disabled
FCMEN(1): Fail-Safe Clock Monitor Enable bit
1 = Fail-Safe Clock Monitor enabled
0 = Fail-Safe Clock Monitor disabled
PRICLKEN: Primary Clock Enable bit
1 = Primary Clock is always enabled
0 = Primary Clock can be disabled by software
PLLCFG: 4 x PLL Enable bit
1 = 4 x PLL always enabled, Oscillator multiplied by 4
0 = 4 x PLL is under software control, PLLEN (OSCTUNE<6>)
FOSC<3:0>: Oscillator Selection bits
1111 = External RC oscillator, CLKOUT function on RA6
1110 = External RC oscillator, CLKOUT function on RA6
1101 = EC oscillator (low power)
1100 = EC oscillator, CLKOUT function on OSC2 (low power)
1011 = EC oscillator (medium power, 4 MHz-16 MHz)
1010 = EC oscillator, CLKOUT function on OSC2 (medium power, 4 MHz-16 MHz)
1001 = Internal oscillator block, CLKOUT function on OSC2
1000 = Internal oscillator block
0111 = External RC oscillator
0110 = External RC oscillator, CLKOUT function on OSC2
0101 = EC oscillator (high power, >16 MHz)
0100 = EC oscillator, CLKOUT function on OSC2 (high power, >16 MHz)
0011= HS oscillator (medium power, 4 MHz - 16 MHz)
0010= HS oscillator (high power, >16 MHz)
0001= XT oscillator
0000= LP oscillator
When FOSC<3:0> is configured for HS, XT, or LS oscillator and FCMEN bit is set, then the IESO bit
should also be set to prevent a false failed clock indication and to enable automatic clock switch over from
the internal oscillator block to the external oscillator when the OST times out.
2010 Microchip Technology Inc.
Preliminary
DS41412A-page 353