mc9s08sh8mwjr Freescale Semiconductor, Inc, mc9s08sh8mwjr Datasheet - Page 81

• Manufacturer Part Number: mc9s08sh8mwjr
• Description: S08sh 5-volt 8-bit Microcontrollers With Sci, Spi, I2c, Adc And Analog Comparators
• Manufacturer: Freescale Semiconductor, Inc

1
6.6.1
Port A is controlled by the registers listed below.
The pins PTA4 and PTA5 are unique. PTA4 is output-only, so the control bits for the input function will
not have any effect on this pin. PTA5, when configured as an output, is open drain.
6.6.1.1
Freescale Semiconductor
PTAD[7:0]
Reset:
Reads of bit PTAD4 always return the contents of PTAD4, regardless of the value stored in bit PTADD4.
Field
7:0
W
R
PTAD7
Port A Registers
Port A Data Register Bits — For port A pins that are inputs, reads return the logic level on the pin. For port A
pins that are configured as outputs, reads return the last value written to this register.
Writes are latched into all bits of this register. For port A pins that are configured as outputs, the logic level is
driven out the corresponding MCU pin.
Reset forces PTAD to all 0s, but these 0s are not driven out the corresponding pins because reset also configures
all port pins as high-impedance inputs with pull-ups/pull-downs disabled.
Port A Data Register (PTAD)
0
7
This PTA5 pin does not contain a clamp diode to V
driven above V
When the internal pullup device is enabled on PTA5 when used as an input
or open drain output the voltage measured on PTA5 will not be pulled to
V
pin is required to drive to a V
DD
. The internal gates connected to this pin are pulled to V
PTAD6
0
6
DD
Table 6-2. PTAD Register Field Descriptions
.
Figure 6-3. Port A Data Register (PTAD)
MC9S08SH32 Series Data Sheet, Rev. 2
PTAD5
0
5
DD
PRELIMINARY
PTAD4
level an external pullup should be used.
NOTE
0
4
1
Description
PTAD3
3
0
DD
and should not be
PTAD2
Chapter 6 Parallel Input/Output Control
DD
0
2
. If the PTA5
PTAD1
0
1
PTAD0
0
0
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