PIC18C658T-ESLASHCL datasheet(129/366 Pages) MICROCHIP

129 / 366 page

 2000 Microchip Technology Inc.

Advanced Information

DS30475A-page 129

PIC18CXX8

14.3.3

SOFTWARE INTERRUPT

When the Capture mode is changed, a false capture

interrupt may be generated. The user should keep bit

CCP1IE (PIE registers) clear to avoid false interrupts

and should clear the flag bit CCP1IF, following any

such change in operating mode.

14.3.4

CCP PRESCALER

There are four prescaler settings, specified by bits

CCP1M3:CCP1M0. Whenever the CCP module is

turned off, or the CCP module is not in Capture mode,

the prescaler counter is cleared. This means that any

RESET will clear the prescaler counter.

Switching from one capture prescaler to another may

generate an interrupt. Also, the prescaler counter will

not be cleared; therefore, the first capture may be from

a non-zero prescaler. Example 14-1 shows the recom-

mended method for switching between capture pres-

calers. This example also clears the prescaler counter

and will not generate the “false” interrupt.

14.3.5

CAN MESSAGE RECEIVED

The CAN capture event occurs when a message is

received in either receive buffer. The CAN module pro-

vides a rising edge to the CCP module to cause a cap-

ture event. This feature is provided to time-stamp the

received CAN messages.

EXAMPLE 14-1: CHANGING BETWEEN

CAPTURE PRESCALERS

FIGURE 14-1: CAPTURE MODE OPERATION BLOCK DIAGRAM

CLRF

CCP1CON, F

; Turn CCP module off

MOVLW

NEW_CAPT_PS ; Load WREG with the

; new prescaler mode

; value and CCP ON

MOVWF

CCP1CON

; Load CCP1CON with

; this value

CCPR1H

CCPR1L

TMR1H

TMR1L

Set Flag bit CCP1IF

TMR3

Enable

Q’s

CCP1M3:CCP1M0

CCP1 Pin

Prescaler

÷ 1, 4, 16

and

edge detect

TMR3H

TMR3L

TMR1

Enable

T3CCP2

CCPR2H

CCPR2L

TMR1H

TMR1L

Set Flag bit CCP2IF

TMR3

Enable

Q’s

CCP2M3:CCP2M0

CCP2 Pin

Prescaler

÷ 1, 4, 16

and

edge detect

TMR3H

TMR3L

TMR1

Enable

T3CCP2

T3CCP1

T3CCP2

T3CCP1

RXB0IF or

RXB1IF

CCP1CON<3:0>

Note:

I/O pins have diode protection to VDD and VSS.

PIC18C658T-E/CL Datasheet(PDF) 129 Page - Microchip Technology

PIC18C658T-E/CL Datasheet(HTML) 129 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