Datasheet

PIC16C712/716
DS41106C-page 50  1999-2013 Microchip Technology Inc.
8.4 A/D Conversions
8.5 Use of the CCP Trigger
An A/D conversion can be started by the “Special Event
Trigger” of the CCP1 module. This requires that the
CCP1M3:CCP1M0 bits (CCP1CON<3:0>) be
programmed as 1011 and that the A/D module is
enabled (ADON bit is set). When the trigger occurs, the
GO/DONE
bit will be set, starting the A/D conversion,
and the Timer1 counter will be reset to zero. Timer1 is
reset to automatically repeat the A/D acquisition period
with minimal software overhead (moving the ADRES to
the desired location). The appropriate analog input
channel must be selected and the minimum acquisition
done before the “Special Event Trigger” sets the GO/
DONE
bit (starts a conversion).
If the A/D module is not enabled (ADON is cleared),
then the “Special Event Trigger” will be ignored by the
A/D module, but will still reset the Timer1 counter.
TABLE 8-2: SUMMARY OF A/D REGISTERS
Note: The GO/DONE bit should NOT be set in
the same instruction that turns on the A/D.
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
05h PORTA
— — —
(1)
RA4 RA3 RA2 RA1 RA0
--xx xxxx --xu uuuu
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
1Eh
ADRES A/D Result Register xxxx xxxx uuuu uuuu
1Fh
ADCON0 ADCS1 ADCS0 CHS2 CHS1 CHS0 GO/DONE
—ADON0000 00-0 0000 00-0
85h TRISA
— — —
(1)
PORTA Data Direction Register
---1 1111 ---1 1111
8Ch
PIE1
—
ADIE
— — — CCP1IE TMR2IE TMR1IE -0-- -000 -0-- 0000
9Fh
ADCON1
— — — — — PCFG2 PCFG1 PCFG0 ---- -000 ---- -000
Legend: x = unknown, u = unchanged, — = unimplemented read as ‘0’. Shaded cells are not used for A/D conversion.
Note 1: Reserved bits; Do Not Use.