PIC16C56-RCI Datasheet, PDF (40/194 Pages) Microchip Technology – EPROM/ROM-Based 8-bit CMOS Microcontroller Series

PIC16C5X
FIGURE 8-3:
TIMER0 TIMING: INTERNAL CLOCK/NO PRESCALER
PC
(Program
Counter)
Instruction
Fetch
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
PC-1
PC
PC+1
PC+2
PC+3
PC+4
PC+5
MOVWF TMR0 MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
PC+6
Timer0
T0
Instruction
Executed
T0+1
T0+2
NT0
NT0
NT0
NT0+1
NT0+2
Write TMR0
executed
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
Read TMR0
reads NT0 + 1 reads NT0 + 2
FIGURE 8-4:
TIMER0 TIMING: INTERNAL CLOCK/PRESCALER 1:2
PC
(Program
Counter)
Instruction
Fetch
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
PC-1
PC
PC+1
PC+2
PC+3
PC+4
PC+5
MOVWF TMR0 MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
PC+6
Timer0
T0
T0+1
NT0
NT0+1
T0
Instruction
Execute
Write TMR0
executed
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Read TMR0
reads NT0 + 1
TABLE 8-1: REGISTERS ASSOCIATED WITH TIMER0
Address
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
01h
TMR0 Timer0 - 8-bit real-time clock/counter
N/A
OPTION
—
— T0CS T0SE PSA PS2 PS1 PS0
Legend: x = unknown, u = unchanged, - = unimplemented. Shaded cells not used by Timer0.
Value on
Power-on
Reset
xxxx xxxx
--11 1111
Value on
MCLR and
WDT Reset
uuuu uuuu
--11 1111
DS30453D-page 38
Preliminary
© 2002 Microchip Technology Inc.