© 2005 Microchip Technology Inc.

DS80172C-page 9

PIC18F8720/8620/6720/6620

10. Module: Timer0 Block Diagram in 8-Bit

and 16-Bit Modes

The PSA multiplexor bit values in Figures 11-1 and

11-2 do not match the text description of the

Timer0 PSA bit in the T0CON register.

The bit values have been corrected by swapping

the values as shown below (correct values are

shown in bold text):

FIGURE 11-1:

TIMER0 BLOCK DIAGRAM IN 8-BIT MODE

FIGURE 11-2:

TIMER0 BLOCK DIAGRAM IN 16-BIT MODE

Note:

Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.

RA4/T0CKI pin

T0SE

0

1

1

0

T0CS

Programmable

Prescaler

Sync with

Internal

Clocks

TMR0

Data Bus

8

PSA

T0PS2, T0PS1, T0PS0

Set Interrupt

Flag bit TMR0IF

on Overflow

3

Note:

Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.

RA4/T0CKI

T0SE

0

1

1

0

T0CS

Programmable

Prescaler

Sync with

Internal

Clocks

TMR0L

Data Bus<7:0>

8

PSA

T0PS2, T0PS1, T0PS0

Set Interrupt

Flag bit TMR0IF

on Overflow

3

TMR0

TMR0H

High Byte

8

8

8

Read TMR0L

Write TMR0L

pin