Datasheet

PIC12F510/16F506
DS41268D-page 40 © 2007 Microchip Technology Inc.
FIGURE 6-2: TIMER0 TIMING: INTERNAL CLOCK/NO PRESCALE
FIGURE 6-3: TIMER0 TIMING: INTERNAL CLOCK/PRESCALE 1:2
TABLE 6-1: REGISTERS ASSOCIATED WITH TIMER0
Addr Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Value on
Power-On
Reset
Value on
All Other
Resets
01h TMR0 Timer0 – 8-bit Real-Time Clock/Counter xxxx xxxx uuuu uuuu
07h
CM1CON0
(2)
C1OUT C1OUTEN C1POL C1T0CS C1ON C1NREF C1PREF C1WU
1111 1111 uuuu uuuu
08h CM1CON0
(3)
C1OUT C1OUTEN C1POL C1T0CS C1ON C1NREF C1PREF C1WU 1111 1111 uuuu uuuu
N/A OPTION
GPWU GPPU T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111
N/A TRISGPIO
(1)
— — I/O Control Register ---- 1111 --11 1111
Legend: Shaded cells not used by Timer0, – = unimplemented, x = unknown, u = unchanged.
Note 1: The TRIS of the T0CKI pin is overridden when T0CS = 1.
2: For PIC12F510.
3: For PIC16F506.
PC - 1
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Instruction
Fetch
Timer0
PC PC + 1 PC + 2 PC + 3 PC + 4 PC + 6
T0
T0 + 1 T0 + 2 NT0
NT0 + 1
NT0 + 2
MOVWF TMR0 MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
Write TMR0
executed
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0 + 1
Read TMR0
reads NT0 + 2
Instruction
Executed
PC + 5
PC
(Program
Counter)
PC - 1
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Instruction
Fetch
Timer0
PC PC + 1 PC + 2 PC + 3 PC + 4 PC + 6
T0
T0 + 1 NT0
NT0 + 1
MOVWF TMR0 MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
Write TMR0
executed
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0 + 1
Read TMR0
reads NT0 + 2
Instruction
Executed
PC + 5
PC
(Program
Counter)