Datasheet

PIC14000
DS40122B-page 32
Preliminary
 1996 Microchip Technology Inc.
5.3 POR
TD and TRISD
PORTD is an 8-bit port that may be used for general
purpose I/O. Four pins can be configured as analog
inputs.
FIGURE 5-8: BLOCK DIAGRAM OF PORTD<7:4> PINS
FIGURE 5-9: BLOCK DIAGRAM OF PORTD<3:2> PINS
D
Q
CK
Q
D
Q
CK
Q
D
Q
EN
Analog Input Mode
Data
Bus
Write
PORTD
Write
TRISD
Read
TRISD
Read
PortD
To A/D Converter
Note: I/O pins have protection diodes to V
DD and VSS.
P
N
I/O
Pin
V
SS
VDD
Schmitt Trigger
Input Buffer
D
Q
CK
Q
D
Q
CK
Q
D
Q
EN
Data
Bus
Write
PORTD
Write
TRISD
Read
TRISD
I/O
Pin
Read
PORTD
Read PORTD
1. I/O pins have protection diodes to VDD and VSS.
2. If CMBOE (CMCON<5>) is set to ‘1’, RD2 becomes CMPB,
RD3 becomes REFB, ignoring the PORTD<3:2> data and
TRISD<3:2> register settings.
Schmitt Trigger
Input Buffer