PIC12F508/509/16F505
REGISTER 4-4:
OPTION REGISTER (PIC16F505)
W-1
RBWU
bit 7
W-1
W-1
W-1
W-1
W-1
PS2
W-1
PS1
W-1
PS0
bit 0
RBPU
T0CS
T0SE
PSA
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2-0
RBWU: Enable Wake-up on Pin Change bit (RB0, RB1, RB3, RB4)
1= Disabled
0= Enabled
RBPU: Enable Weak Pull-ups bit (RB0, RB1, RB3, RB4)
1= Disabled
0= Enabled
T0CS: Timer0 clock Source Select bit
1= Transition on T0CKI pin (overrides TRIS on the T0CKI pin)
0= Transition on internal instruction cycle clock, FOSC/4
T0SE: Timer0 Source Edge Select bit
1= Increment on high-to-low transition on the T0CKI pin
0= Increment on low-to-high transition on the T0CKI pin
PSA: Prescaler Assignment bit
1= Prescaler assigned to the WDT
0= Prescaler assigned to Timer0
PS<2:0>: Prescaler Rate Select bits
Bit Value Timer0 Rate WDT Rate
000
001
010
011
100
101
110
111
1 : 2
1 : 1
1 : 4
1 : 2
1 : 8
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 23
MICROCHIP [ MICROCHIP ]
