em78p134n ELAN Microelectronics Corp, em78p134n Datasheet - Page 25

• Manufacturer Part Number: em78p134n
• Description: 8-bit Microcontroller With Otp Rom
• Manufacturer: ELAN Microelectronics Corp

Product Specification (V1.6) 06.02.2010
(This specification is subject to change without further notice)
5.4 I/O Ports
The I/O registers, Port 6, is bidirectional tri-state I/O port. Port 6 can be pulled-high
internally by software except P63. In addition, Port 6 can also have open-drain output
by software except P63. Input status changed interrupt (or wake-up) function is
available from Port 6. P62 ~ P60 pins can be pulled-down by software. Each I/O pin
can be defined as "input" or "output" pin by the I/O control register (IOC6) except P63.
The I/O registers and I/O control registers are both readable and writable. The I/O
interface circuits for Port 6 are shown in Figure 5-5, Figure 5-6 and Figure 5-7
respectively.
Note: Pull-down is not shown in the figure.
PORT
Figure 5-5 The Circuit of I/O Port and I/O Control Register for Port 6
0
1
M
U
X
Q
Q
Q
_
Q
PCRD
_
C
P
R
L
P
R
C
L
CLK
CLK
8-Bit Microcontroller with OTP ROM
D
D
PDRD
PCWR
PDWR
EM78P134N
IOD
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