Datasheet

PIC16C5X
DS30453E-page 30 Preliminary  1997-2013 Microchip Technology Inc.
6.4 OPTION Register
The OPTION Register is a 6-bit wide, write-only regis-
ter which contains various control bits to configure the
Timer0/WDT prescaler and Timer0.
By executing the OPTION instruction, the contents of
the W Register will be transferred to the OPTION Reg-
ister. A RESET sets the OPTION<5:0> bits.
REGISTER 6-2: OPTION REGISTER
U-0 U-0 W-1 W-1 W-1 W-1 W-1 W-1
— — T0CS TOSE PSA PS2 PS1 PS0
bit 7 bit 0
bit 7-6: Unimplemented: Read as ‘0’
bit 5: T0CS: Timer0 clock source select bit
1 = Transition on T0CKI pin
0 = Internal instruction cycle clock (CLKOUT)
bit 4: T0SE: Timer0 source edge select bit
1 = Increment on high-to-low transition on T0CKI pin
0 = Increment on low-to-high transition on T0CKI pin
bit 3: PSA: Prescaler assignment bit
1 = Prescaler assigned to the WDT
0 = Prescaler assigned to Timer0
bit 2-0: PS<2:0>: Prescaler rate select bits
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
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