PIC16F882_09 Datasheet, PDF (127/328 Pages) Microchip Technology – 28/40/44-Pin, Enhanced Flash-Based 8-Bit CMOS Microcontrollers with nanoWatt Technology

PIC16F882/883/884/886/887
11.2 Capture/Compare/PWM (CCP2)
The Capture/Compare/PWM module is a peripheral
which allows the user to time and control different
events. In Capture mode, the peripheral allows the
timing of the duration of an event. The Compare mode
allows the user to trigger an external event when a
predetermined amount of time has expired. The PWM
mode can generate a Pulse-Width Modulated signal of
varying frequency and duty cycle.
The timer resources used by the module are shown in
Table 11-2.
Additional information on CCP modules is available in
the Application Note AN594, “Using the CCP Modules”
(DS00594).
TABLE 11-2: CCP MODE – TIMER
RESOURCES REQUIRED
CCP Mode
Timer Resource
Capture
Compare
PWM
Timer1
Timer1
Timer2
REGISTER 11-2: CCP2CON: CCP2 CONTROL REGISTER
U-0
—
bit 7
U-0
R/W-0
R/W-0
R/W-0
—
DC2B1
DC2B0
CCP2M3
R/W-0
CCP2M2
R/W-0
CCP2M1
R/W-0
CCP2M0
bit 0
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
bit 5-4
bit 3-0
Unimplemented: Read as ‘0’
DC2B<1:0>: PWM Duty Cycle Least Significant bits
Capture mode:
Unused.
Compare mode:
Unused.
PWM mode:
These bits are the two LSbs of the PWM duty cycle. The eight MSbs are found in CCPR2L.
CCP2M<3:0>: CCP2 Mode Select bits
0000 = Capture/Compare/PWM off (resets CCP2 module)
0001 = Unused (reserved)
0010 = Unused (reserved)
0011 = Unused (reserved)
0100 = Capture mode, every falling edge
0101 = Capture mode, every rising edge
0110 = Capture mode, every 4th rising edge
0111 = Capture mode, every 16th rising edge
1000 = Compare mode, set output on match (CCP2IF bit is set)
1001 = Compare mode, clear output on match (CCP2IF bit is set)
1010 = Compare mode, generate software interrupt on match (CCP2IF bit is set, CCP2 pin
is unaffected)
1011 = Compare mode, trigger special event (CCP2IF bit is set, TMR1 is reset and A/D
conversion is started if the ADC module is enabled. CCP2 pin is unaffected.)
11xx = PWM mode.
© 2009 Microchip Technology Inc.
DS41291F-page 125