Datasheet

 2002 Microchip Technology Inc. DS30325B-page 53
PIC16F7X
8.0 CAPTURE/COMPARE/PWM
MODULES
Each Capture/Compare/PWM (CCP) module contains
a 16-bit register which can operate as a:
• 16-bit Capture register
• 16-bit Compare register
• PWM Master/Slave Duty Cycle register
Both the CCP1 and CCP2 modules are identical in
operation, with the exception being the operation of the
special event trigger. Table 8-1 and Table 8-2 show the
resources and interactions of the CCP module(s). In
the following sections, the operation of a CCP module
is described with respect to CCP1. CCP2 operates the
same as CCP1, except where noted.
8.1 CCP1 Module
Capture/Compare/PWM Register1 (CCPR1) is com-
prised of two 8-bit registers: CCPR1L (low byte) and
CCPR1H (high byte). The CCP1CON register controls
the operation of CCP1. The special event trigger is
generated by a compare match and will clear both
TMR1H and TMR1L registers.
8.2 CCP2 Module
Capture/Compare/PWM Register1 (CCPR1) is com-
prised of two 8-bit registers: CCPR1L (low byte) and
CCPR1H (high byte). The CCP2CON register controls
the operation of CCP2. The special event trigger is
generated by a compare match; it will clear both
TMR1H and TMR1L registers, and start an A/D conver-
sion (if the A/D module is enabled).
Additional information on CCP modules is available in
the PICmicro™ Mid-Range MCU Family Reference
Manual (DS33023) and in Application Note AN594,
“Using the CCP Modules” (DS00594).
TABLE 8-1: CCP MODE - TIMER
RESOURCES REQUIRED
TABLE 8-2: INTERACTION OF TWO CCP MODULES
CCP Mode Timer Resource
Capture
Compare
PWM
Timer1
Timer1
Timer2
CCPx Mode CCPy Mode Interaction
Capture Capture Same TMR1 time-base.
Capture Compare
Same TMR1 time-base.
Compare Compare
Same TMR1 time-base.
PWM PWM The PWMs will have the same frequency and update rate (TMR2 interrupt).
The rising edges are aligned.
PWM Capture None.
PWM Compare None.