Datasheet

 1999-2013 Microchip Technology Inc. DS41106C-page 43
PIC16C712/716
7.3.3 SET-UP FOR PWM OPERATION
The following steps should be taken when configuring
the CCP module for PWM operation:
1. Set the PWM period by writing to the PR2
register.
2. Set the PWM duty cycle by writing to the
CCPR1L register and CCP1CON<5:4> bits.
3. Make the CCP1 pin an output by clearing the
TRISCCP<2> bit.
4. Set the TMR2 prescale value and enable Timer2
by writing to T2CON.
5. Configure the CCP1 module for PWM operation.
TABLE 7-3: EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 20 MHz
TABLE 7-4: REGISTERS ASSOCIATED WITH PWM AND TIMER2
PWM Frequency 1.22 kHz 4.88 kHz 19.53 kHz 78.12 kHz 156.3 kHz 208.3 kHz
Timer Prescaler (1, 4, 16) 16 4 1 1 1 1
PR2 Value 0xFF 0xFF 0xFF 0x3F 0x1F 0x17
Maximum Resolution (bits) 10 10 10 8 7 5.5
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Value on
POR,
BOR
Value on
all other
Resets
07h DATACCP
— — — — —
DCCP — DT1CK
xxxx xxxx xxxx xuxu
0Bh,8Bh INTCON GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u
0Ch PIR1
— ADIF — — — CCP1IF TMR2IF TMR1IF -0-- -000 -0-- -000
11h TMR2 Timer2 Module’s Register 0000 0000 0000 0000
12h T2CON
— TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
15h CCPR1L Capture/Compare/PWM Register 1 (LSB) xxxx xxxx uuuu uuuu
16h CCPR1H Capture/Compare/PWM Register 1 (MSB) xxxx xxxx uuuu uuuu
17h CCP1CON
— — DC1B1 DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
87h TRISCCP
— — — — —
TCCP
—
TT1CK xxxx x1x1 xxxx x1x1
8Ch PIE1 — ADIE — — — CCP1IE TMR2IE TMR1IE -0-- -000 -0-- -000
92h PR2 Timer2 Module’s Period Register 1111 1111 1111 1111
Legend: x = unknown, u = unchanged, — = unimplemented read as ‘0’. Shaded cells are not used by PWM and Timer2.