Datasheet

PIC16F716
DS41206B-page 12 © 2007 Microchip Technology Inc.
2.2.2.2 OPTION Register
The OPTION register is a readable and writable regis-
ter, which contains various control bits to configure the
TMR0 prescaler/WDT postscaler (single assignable
register known also as the prescaler), the External INT
Interrupt, TMR0 and the weak pull-ups on PORTB.
Note: To achieve a 1:1 prescaler assignment for
the Timer0 register, assign the prescaler
to the Watchdog Timer.
REGISTER 2-2: OPTION_REG: OPTION REGISTER
R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1
RBPU
INTEDG T0CS T0SE PSA PS2 PS1 PS0
bit 7 bit 0
Legend:
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 RBPU
: PORTB Pull-up Enable bit
1 = PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled by individual PORT latch values
bit 6 INTEDG: Interrupt Edge Select bit
1 = Interrupt on rising edge of RB0/INT pin
0 = Interrupt on falling edge of RB0/INT pin
bit 5 T0CS: Timer0 Clock Source Select bit
1 = Transition on RA4/T0CKI pin
0 = Internal instruction cycle clock (FOSC/4)
bit 4 T0SE: Timer0 Source Edge Select bit
1 = Increment on high-to-low transition on RA4/T0CKI pin
0 = Increment on low-to-high transition on RA4/T0CKI pin
bit 3 PSA: Prescaler Assignment bit
1 = Prescaler is assigned to the WDT
0 = Prescaler is assigned to the Timer0 module
bit 2-0 PS<2:0>: Prescaler Rate Select bits
000
001
010
011
100
101
110
111
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
1 : 1
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
Bit Value Timer0 Rate WDT Rate