Datasheet

PIC16C62B/72A
 1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 35
7.2 Compare Mode
In Compare mode, the 16-bit CCPR1 register value is
constantly compared against the TMR1 register pair
value. When a match occurs, the RC2/CCP1 pin is:
•driven High
• driven Low
• remains Unchanged
The action on the pin is based on the value of control
bits CCP1M3:CCP1M0 (CCP1CON<3:0>). The inter-
rupt flag bit, CCP1IF, is set on all compare matches.
FIGURE 7-2: COMPARE MODE
OPERATION BLOCK
DIAGRAM
7.2.1 CCP PIN CONFIGURATION
The user must configure the RC2/CCP1 pin as an out-
put by clearing the TRISC<2> bit.
7.2.2 TIMER1 MODE SELECTION
Timer1 must be running in Timer mode or Synchro-
nized Counter mode if the CCP module is using the
compare feature. In Asynchronous Counter mode, the
compare operation may not work.
7.2.3 SOFTWARE INTERRUPT MODE
When a generated software interrupt is chosen, the
CCP1 pin is not affected. Only a CCP interrupt is gen-
erated (if enabled).
7.2.4 SPECIAL EVENT TRIGGER
In this mode, an internal hardware trigger is generated,
which may be used to initiate an action.
The special event trigger output of CCP1 resets the
TMR1 register pair. This allows the CCPR1 register to
effectively be a 16-bit programmable period register for
Timer1.
The special trigger output of CCP1 resets the TMR1
register pair and starts an A/D conversion (if the A/D
module is enabled).
TABLE 7-3 REGISTERS ASSOCIATED WITH CAPTURE, COMPARE, AND TIMER1
CCPR1H CCPR1L
TMR1H TMR1L
Comparator
QS
R
Output
Logic
Special Event Trigger
Set flag bit CCP1IF
(PIR1<2>)
match
RC2/CCP1
TRISC<2>
CCP1CON<3:0>
Mode Select
Output Enable
Pin
Special event trigger will:
reset Timer1, but not set interrupt flag bit TMR1IF (PIR1<0>),
and set bit GO/DONE
(ADCON0<2>), which starts an A/D
conversion
Note: Clearing the CCP1CON register will force
the RC2/CCP1 compare output latch to the
default low level. This is not the data latch.
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
0Bh,8Bh INTCON GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u
0Ch PIR1
— ADIF — — SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 -0-- 0000
8Ch PIE1
— ADIE — — SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000
87h TRISC PORTC Data Direction Register 1111 1111 1111 1111
0Eh TMR1L Holding register for the Least Significant Byte of the 16-bit TMR1 register xxxx xxxx uuuu uuuu
0Fh TMR1H Holding register for the Most Significant Byte of the 16-bit TMR1register xxxx xxxx uuuu uuuu
10h T1CON
— — T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
15h CCPR1L Capture/Compare/PWM register1 (LSB) xxxx xxxx uuuu uuuu
16h CCPR1H Capture/Compare/PWM register1 (MSB) xxxx xxxx uuuu uuuu
17h CCP1CON
— — CCP1X CCP1Y CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
Legend: x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used by Capture and Timer1.