PIC18C242 MICROCHIP [Microchip Technology], PIC18C242 Datasheet - Page 116

• Manufacturer Part Number: PIC18C242
• Description: High-Performance Microcontrollers with 10-Bit A/D
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18CXX2
13.5.3
The following steps should be taken when configuring
the CCP module for PWM operation:
1.
2.
3.
4.
5.
TABLE 13-4:
TABLE 13-5:
DS39026B-page 116
Timer Prescaler (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
INTCON
PIR1
PIE1
IPR1
TRISC
TMR2
PR2
T2CON
CCPR1L
CCPR1H
CCP1CON
CCPR2L
CCPR2H
CCP2CON
Legend:
Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
Name
Set the PWM period by writing to the PR2 regis-
ter.
Set the PWM duty cycle by writing to the
CCPR1L register and CCP1CON<5:4> bits.
Make the CCP1 pin an output by clearing the
TRISC<2> bit.
Set the TMR2 prescale value and enable Timer2
by writing to T2CON.
Configure the CCP1 module for PWM operation.
SET-UP FOR PWM OPERATION
PWM Frequency
Shaded cells are not used by PWM and Timer2.
x = unknown, u = unchanged,
GIE/
GIEH
PSPIF
PSPIE
PSPIP
PORTC Data Direction Register
Timer2 module’s register
Timer2 module’s period register
Capture/Compare/PWM register1 (LSB)
Capture/Compare/PWM register1 (MSB)
Capture/Compare/PWM register2 (LSB)
Capture/Compare/PWM register2 (MSB)
Bit 7
—
—
—
(1)
(1)
(1)
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 40 MHz
REGISTERS ASSOCIATED WITH PWM AND TIMER2
PEIE/
GIEL
ADIF
ADIE
ADIP
TOUTPS3
Bit 6
—
—
TMR0IE
RCIF
RCIE
RCIP
TOUTPS2
DC1B1
DC2B1
Bit 5
—
2.44 kHz
= unimplemented read as ’0’.
0xFF
16
10
INT0IE
TXIF
TXIE
TXIP
TOUTPS1
DC1B0
DC2B0
Bit 4
Preliminary
9.76 kHz
0xFF
RBIE
SSPIF
SSPIE
SSPIP
TOUTPS0
CCP1M3
CCP2M3
10
4
Bit 3
19.53 kHz
TMR0IF
CCP1IF
CCP1IE
CCP1IP
TMR2ON
CCP1M2
CCP2M2
0xFF
Bit 2
10
1
INT0IF
TMR2IF
TMR2IE
TMR2IP
T2CKPS1
CCP1M1
CCP2M1
Bit 1
39.06 kHz
0x3F
1
8
RBIF
TMR1IF
TMR1IE
TMR1IP
T2CKPS0
CCP1M0
CCP2M0
Bit 0
7/99 Microchip Technology Inc.
78.12 kHz
0x1F
1
7
0000 000x
0000 0000
0000 0000
0000 0000
1111 1111
0000 0000
1111 1111
-000 0000
xxxx xxxx
xxxx xxxx
--00 0000
xxxx xxxx
xxxx xxxx
--00 0000
Value on
POR,
BOR
208.3 kHz
0x17
5.5
1
0000 000u
0000 0000
0000 0000
0000 0000
1111 1111
0000 0000
1111 1111
-000 0000
uuuu uuuu
uuuu uuuu
--00 0000
uuuu uuuu
uuuu uuuu
--00 0000
Value on
all other
resets