PIC18F4580-ESLASHML datasheet(163/490 Pages) MICROCHIP

163 / 490 page

DS39637D-page 163

PIC18F2480/2580/4480/4580

15.0 TIMER3 MODULE

The Timer3 module timer/counter incorporates these

features:

• Software-selectable operation as a 16-bit timer or

counter

• Readable and writable 8-bit registers (TMR3H

and TMR3L)

• Selectable clock source (internal or external) with

device clock or Timer1 oscillator internal options

• Interrupt-on-overflow

• Module Reset on CCP Special Event Trigger

A simplified block diagram of the Timer3 module is

shown in Figure 15-1. A block diagram of the module’s

operation in Read/Write mode is shown in Figure 15-2.

The Timer3 module is controlled through the T3CON

options for the CCP modules (see Section 16.1.1

“CCP Modules and Timer Resources” for more

information).

T3CON: TIMER3 CONTROL REGISTER

R/W-0

RD16

T3ECCP1(1)

T3CKPS1

T3CKPS0

T3CCP1(1)

T3SYNC

TMR3CS

TMR3ON

bit 7

bit 0

Legend:

R = Readable bit

W = Writable bit

U = Unimplemented bit, read as ‘0’

-n = Value at POR

‘1’ = Bit is set

‘0’ = Bit is cleared

x = Bit is unknown

bit 7

RD16: 16-Bit Read/Write Mode Enable bit

1 = Enables register read/write of Timer3 in one 16-bit operation

0 = Enables register read/write of Timer3 in two 8-bit operations

bit 6,3

T3ECCP1:T3CCP1: Timer3 and Timer1 to CCP/ECCP Enable bits(1)

1x = Timer3 is the capture/compare clock source for both CCP and ECCP modules

01 = Timer3 is the capture/compare clock source for ECCP;

Timer1 is the capture/compare clock source for CCP

00 = Timer1 is the capture/compare clock source for both CCP and ECCP modules

bit 5-4

T3CKPS<1:0>: Timer3 Input Clock Prescale Select bits

11 = 1:8 Prescale value

10 = 1:4 Prescale value

01 = 1:2 Prescale value

00 = 1:1 Prescale value

bit 2

T3SYNC: Timer3 External Clock Input Synchronization Control bit

(Not usable if the device clock comes from Timer1/Timer3.)

When TMR3CS = 1:

1 = Do not synchronize external clock input

0 = Synchronize external clock input

When TMR3CS = 0:

This bit is ignored. Timer3 uses the internal clock when TMR3CS = 0.

bit 1

TMR3CS: Timer3 Clock Source Select bit

1 = External clock input from Timer1 oscillator or T13CKI (on the rising edge after the first falling edge)

0 = Internal clock (FOSC/4)

bit 0

TMR3ON: Timer3 On bit

1 = Enables Timer3

0 = Stops Timer3

Note 1:

These bits and the ECCP module are available on PIC18F4X80 devices only.

PIC18F4580-E/ML Datasheet(PDF) 163 Page - Microchip Technology

PIC18F4580-E/ML Datasheet(HTML) 163 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL