PIC16F688-I/P Microchip Technology Inc., PIC16F688-I/P Datasheet - Page 16

• Manufacturer Part Number: PIC16F688-I/P
• Description: 14 PIN, 7 KB FLASH, 256 RAM, 12 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F688-I/P

• A/d Inputs: 8-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 5 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 12
• Interface: USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 14-pin PDIP
• Programmable Memory: 7K Bytes
• Ram Size: 256 Bytes
• Speed: 20 MHz
• Timers: 1-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PIC16F688
2.2.2.2
The OPTION register is a readable and writable
register, which contains various control bits to
configure:
• Timer0/WDT prescaler
• External RA2/INT interrupt
• Timer0
• Weak pull-ups on PORTA
REGISTER 2-2:
DS41203C-page 14
bit 7
Legend:
R = Readable bit
-n = Value at POR
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2-0
R/W-1
RAPU
OPTION Register
RAPU: PORTA Pull-up Enable bit
1 = PORTA pull-ups are disabled
0 = PORTA pull-ups are enabled by individual PORT latch values
INTEDG: Interrupt Edge Select bit
1 = Interrupt on rising edge of RA2/INT pin
0 = Interrupt on falling edge of RA2/INT pin
T0CS: Timer0 Clock Source Select bit
1 = Transition on RA2/T0CKI pin
0 = Internal instruction cycle clock (F
T0SE: Timer0 Source Edge Select bit
1 = Increment on high-to-low transition on RA2/T0CKI pin
0 = Increment on low-to-high transition on RA2/T0CKI pin
PSA: Prescaler Assignment bit
1 = Prescaler is assigned to the WDT
0 = Prescaler is assigned to the Timer0 module
PS<2:0>: Prescaler Rate Select bits
INTEDG
R/W-1
OPTION_REG: OPTION REGISTER
Bit Value
000
001
010
011
100
101
110
111
W = Writable bit
‘1’ = Bit is set
R/W-1
T0CS
Timer0 Rate
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
R/W-1
T0SE
WDT Rate
1 : 1
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
OSC
/4)
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
R/W-1
PSA
Note:
To achieve a 1:1 prescaler assignment for
Timer0, assign the prescaler to the WDT
by setting PSA bit of the OPTION register
to ‘1’. See Section 5.1.3 “Software
Programmable Prescaler”.
R/W-1
PS2
© 2006 Microchip Technology Inc.
x = Bit is unknown
R/W-1
PS1
R/W-1
PS0
bit 0