PIC16F628A-E/SS Microchip Technology, PIC16F628A-E/SS Datasheet - Page 48

• Manufacturer Part Number: PIC16F628A-E/SS
• Description: IC MCU FLASH 2KX14 EEPROM 20SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F628A-E/SS

• 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
• For Use With: I3DBF648 - BOARD DAUGHTER ICEPIC3AC162053 - HEADER INTERFACE ICD,ICD2 18DIP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Converters: -

PIC16F627A/628A/648A
6.3
An 8-bit counter is available as a prescaler for the
Timer0 module, or as a postscaler for the Watchdog
Timer. A prescaler assignment for the Timer0 module
means that there is no postscaler for the Watchdog
Timer, and vice-versa.
FIGURE 6-1:
DS40044G-page 48
WDT Enable bit
T0CKI
Watchdog
pin
Timer
Timer0 Prescaler
Note:
F
OSC
/4
T0SE, T0CS, PSA, PS<2:0> are bits in the Option Register.
T0SE
BLOCK DIAGRAM OF THE TIMER0/WDT
TMR1 Clock Source
PSA
0
1
.
T0CS
0
1
WDT Postscaler/
TMR0 Prescaler
8-to-1MUX
8
PSA
PSA
1
0
1
0
The PSA and PS<2:0> bits (OPTION<3:0>) determine
the prescaler assignment and prescale ratio.
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (e.g., CLRF 1, MOVWF 1,
BSF 1, x....etc.) will clear the prescaler. When
assigned to WDT, a CLRWDT instruction will clear the
prescaler along with the Watchdog Timer. The prescaler
is not readable or writable.
Time-out
WDT
Cycles
PS<2:0>
SYNC
2
© 2009 Microchip Technology Inc.
TMR0 Reg
Data Bus
8
Set flag bit T0IF
on Overflow