PIC16F628A-I/P Microchip Technology Inc., PIC16F628A-I/P Datasheet - Page 46

• Manufacturer Part Number: PIC16F628A-I/P
• Description: 18 PIN, 3.5 KB FLASH, 224 RAM, 16 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F628A-I/P

• Comparators: 2
• Cpu Speed: 5 MIPS
• Eeprom Memory: 128 Bytes
• Input Output: 16
• Interface: USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 18-pin PDIP
• Programmable Memory: 3.5K Bytes
• Ram Size: 224 Bytes
• Speed: 20 MHz
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PIC16F62X
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:
DS40300C-page 44
WDT Enable bit
T0CKI
Watchdog
Pin
Note 1: T0SE, T0CS, PSA, PS0-PS2 are bits in the Option Register.
Timer
Timer0 Prescaler
F
OSC
/4
T0SE
BLOCK DIAGRAM OF THE TIMER0/WDT
0
1
PSA
.
T0CS
0
1
WDT Postscaler/
TMR0 Prescaler
0
Timeout
WDT
Preliminary
8-to-1MUX
8
1
1
0
PSA
The PSA and PS2:PS0 bits (OPTION<3:0>) determine
the prescaler assignment and prescale ratio.
When assigned to the Timer0 module, all instructions
writing
MOVWF 1, BSF 1, x....etc.) will clear the pres-
caler. When assigned to WDT, a CLRWDT instruction
will clear the prescaler along with the Watchdog Timer.
The prescaler is not readable or writable.
PSA
to
PS0 - PS2
Cycles
SYNC
2
the
TMR0
 2003 Microchip Technology Inc.
TMR0 reg
register
Data Bus
8
Set Flag Bit T0IF
(e.g.,
on Overflow
CLRF 1,