PIC16F628AT-E/SS Microchip Technology, PIC16F628AT-E/SS Datasheet - Page 25

• Manufacturer Part Number: PIC16F628AT-E/SS
• Description: IC,MICROCONTROLLER,8-BIT,PIC CPU,CMOS,SSOP,20PIN,PLASTIC
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F628AT-E/SS

• Rohs Compliant: YES
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Size: 3.5KB (2K x 14)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 224 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 20-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: I3DBF648 - BOARD DAUGHTER ICEPIC3AC162053 - HEADER INTERFACE ICD,ICD2 18DIP
• Data Converters: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

4.2.2.2
The Option register is a readable and writable register,
which contains various control bits to configure the
TMR0/WDT prescaler, the external RB0/INT interrupt,
TMR0 and the weak pull-ups on PORTB.
REGISTER 4-2:
© 2009 Microchip Technology Inc.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2-0
OPTION Register
OPTION_REG – OPTION REGISTER (ADDRESS: 81h, 181h)
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
INTEDG: Interrupt Edge Select bit
1 = Interrupt on rising edge of RB0/INT pin
0 = Interrupt on falling edge of RB0/INT pin
T0CS: TMR0 Clock Source Select bit
1 = Transition on RA4/T0CKI/CMP2 pin
0 = Internal instruction cycle clock (CLKOUT)
T0SE: TMR0 Source Edge Select bit
1 = Increment on high-to-low transition on RA4/T0CKI/CMP2 pin
0 = Increment on low-to-high transition on RA4/T0CKI/CMP2 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
Legend:
R = Readable bit
-n = Value at POR
R/W-1
RBPU
Bit Value TMR0 Rate WDT Rate
000
001
010
011
100
101
110
111
INTEDG
R/W-1
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
R/W-1
T0CS
W = Writable bit
‘1’ = Bit is set
PIC16F627A/628A/648A
1 : 1
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
R/W-1
T0SE
Note:
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
R/W-1
PSA
To achieve a 1:1 prescaler assignment for
TMR0, assign the prescaler to the WDT
(PSA = 1). See Section 6.3.1 “Switching
Prescaler Assignment”.
R/W-1
PS2
x = Bit is unknown
R/W-1
PS1
DS40044G-page 25
R/W-1
PS0
bit 0