PIC16F7X
with minimal software overhead (moving the ADRES to
the desired location). The appropriate analog input
channel must be selected and an appropriate acquisi-
tion time should pass before the “special event trigger”
sets the GO/DONE bit (starts a conversion).
11.7 Use of the CCP Trigger
An A/D conversion can be started by the “special event
trigger” of the CCP2 module. This requires that the
CCP2M3:CCP2M0 bits (CCP2CON<3:0>) be pro-
grammed as 1011and 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
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 11-2: SUMMARY OF A/D REGISTERS
Value on:
POR,
BOR
Value on
all other
RESETS
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0Bh,8Bh,
INTCON
GIE
PEIE TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF 0000 000x 0000 000u
10Bh, 18Bh
(1)
0Ch
0Dh
PIR1
PIR2
PSPIF
ADIF
RCIF
TXIF
SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
CCP2IF ---- ---0 ---- ---0
SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
—
—
—
—
—
—
—
(1)
8Ch
8Dh
1Eh
PIE1
PSPIE
ADIE
RCIE
TXIE
PIE2
—
—
—
—
—
—
—
CCP2IE ---- ---0 ---- ---0
ADRES
A/D Result Register
xxxx xxxx uuuu uuuu
1Fh
9Fh
05h
85h
ADCON0 ADCS1 ADCS0 CHS2
CHS1
—
CHS0 GO/DONE
—
ADON 0000 00-0 0000 00-0
ADCON1
PORTA
TRISA
—
—
—
—
—
—
—
—
PCFG2
RA2
PCFG1 PCFG0 ---- -000 ---- -000
RA5
RA4
RA3
RA1
RA0
RE0
--0x 0000 --0u 0000
--11 1111 --11 1111
PORTA Data Direction Register
(2)
09h
89h
PORTE
—
—
—
—
—
—
RE2
RE1
---- -xxx ---- -uuu
0000 -111 0000 -111
(2)
TRISE
IBF
OBF
IBOV PSPMODE
PORTE Data Direction Bits
Legend: x= unknown, u= unchanged, -= unimplemented, read as '0'. Shaded cells are not used for A/D conversion.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16F73/76; always maintain these bits clear.
2: These registers are reserved on the PIC16F73/76.
DS30325B-page 88
2002 Microchip Technology Inc.