PIC18F2331 Datasheet, PDF (153/396 Pages) Microchip Technology – 28/40/44-Pin Enhanced Flash Microcontrollers with nanoWatt Technology, High Performance PWM and A/D

PIC18F2331/2431/4331/4431
15.0 CAPTURE/COMPARE/PWM
(CCP) MODULES
The CCP (Capture/Compare/PWM) module contains a
16-bit register that can operate as a 16-bit Capture reg-
ister, a 16-bit Compare register or a PWM Master/Slave
Duty Cycle register. Table 15-1 shows the timer
resources required for each of the CCP module modes.
The operation of CCP1 is identical to that of CCP2, with
the exception of the special event trigger. Therefore,
operation of a CCP module is described with respect to
CCP1, except where noted.
REGISTER 15-1:
CCPxCON: CCP MODULE CONTROL REGISTER
U-0
U-0
R/W-0 R/W-0 R/W-0
—
—
DCxB1 DCxB0 CCPxM3
bit 7
R/W-0
CCPxM2
R/W-0
CCPxM1
R/W-0
CCPxM0
bit 0
bit 7-6
bit 5-4
bit 3-0
Unimplemented: Read as ‘0’
DCxB1:DCxB0: PWM Duty Cycle bit1 and bit0
Capture mode:
Unused
Compare mode:
Unused
PWM mode:
These bits are the two LSbs (bit 1 and bit 0) of the 10-bit PWM duty cycle. The upper eight bits
(DCx9:DCx2) of the duty cycle are found in CCPRxL.
CCPxM3:CCPxM0: CCPx Mode Select bits
0000 =Capture/Compare/PWM disabled (resets CCPx module)
0001 =Reserved
0010 =Compare mode, toggle output on match (CCPxIF bit is set)
0011 =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, Initialize CCP pin Low, on compare match force CCP pin High
(CCPxIF bit is set)
1001 =Compare mode, Initialize CCP pin High, on compare match force CCP pin Low
(CCPxIF bit is set)
1010 =Compare mode, Generate software interrupt-on-compare match (CCPxIF bit is set,
CCP pin is unaffected)
1011 =Compare mode, Trigger special event (CCP2IF bit is set)
11xx =PWM mode
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
 2003 Microchip Technology Inc.
Preliminary
DS39616B-page 151