AN201
Rev 1.5 | 83/91
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16.3 Port Description
Each port of PORTA and PORTC contains different multiplexing functions. The specific functions and controls will be discussed in
this section.
16.3.1 PORTA<2:0>
PA<2:0> can be configured as the following functional port.
GPIO
serial port clock for debug (PA0)
Serial port data for Debug (PA1)
External interrupt input (PA2)
External clock source for Timer0 (PA2)
The following figure describes The internal circuit architecture of the port is shown in the below figure.
D
CLK Q
Q
_
RD
TRISA
WR
WPUA
Data
Bus
V
DD
RD
WPUA
WR
PORTA
/RAPU
V
DD
WR
TRISA
RD
PORTA
WR
IOCA
RD
IOCA
Interrupt
On Change
D
Q
Q
_
D
Q
Q
_
RD
PORTA
Qn
T0CKI
(
PA2 Only
)
D
CLK Q
Q
_
D
CLK Q
Q
_
D
CLK Q
Q
_
Figure 29
. PA<2:0> Architecture Diagram