PIC12CE673 MICROCHIP [Microchip Technology], PIC12CE673 Datasheet - Page 34

• Manufacturer Part Number: PIC12CE673
• Description: 8-Pin, 8-Bit CMOS Microcontroller with A/D Converter and EEPROM Data Memory
• Manufacturer: MICROCHIP [Microchip Technology]

PIC12CE67X
7.3
An 8-bit counter is available as a prescaler for the
Timer0 module, or as a postscaler for the Watchdog
Timer, respectively (Figure 7-6). For simplicity, this
counter is being referred to as “prescaler” throughout
this data sheet. Note that there is only one prescaler
available which is mutually exclusively shared between
the Timer0 module and the Watchdog Timer. Thus, a
prescaler assignment for the Timer0 module means
that there is no prescaler for the Watchdog Timer, and
vice-versa.
FIGURE 7-6:
DS40181B-page 34
GP2/T0CKI/
AN2/INT
CLKOUT (=Fosc/4)
WDT Enable bit
Watchdog
Timer
Prescaler
Note: T0CS, T0SE, PSA, PS2:PS0 are (OPTION<5:0>).
BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER
T0SE
0
1
PSA
M
U
X
0
1
T0CS
M
U
X
0
8-bit Prescaler
8 - to - 1MUX
Time-out
8
M U X
WDT
Preliminary
1
0
1
PSA
M
U
X
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 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.
PSA
PS2:PS0
Cycles
SYNC
2
1998 Microchip Technology Inc.
TMR0 reg
Data Bus
8
Set flag bit T0IF
on Overflow