mc9s08rd60fj Freescale Semiconductor, Inc, mc9s08rd60fj Datasheet - Page 111

• Manufacturer Part Number: mc9s08rd60fj
• Description: Hcs08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Chapter 8 Parallel Input/Output
8.1 Introduction
This section explains software controls related to parallel input/output (I/O). The MC9S08RC/RD/RE/RG
has five I/O ports that include a total of 39 general-purpose I/O pins (two of these pins are output only and
one pin is input only). Not all of the ports are available in all packages. See
for more information about the logic and hardware aspects of these pins.
Many of these pins are shared with on-chip peripherals such as timer systems, external interrupts, or
keyboard interrupts. When these other modules are not controlling the port pins, they revert to
general-purpose I/O control. For each I/O pin, a port data bit provides access to input (read) and output
(write) data. A data direction bit controls the direction of the pin and a pullup enable bit enables an internal
pullup device (if the pin is configured as an input).
8.2 Features
Parallel I/O features for the MC9S08RC/RD/RE/RG MCUs, depending on specific device and package
choice, include:
8.3 Pin Descriptions
The MC9S08RC/RD/RE/RG has a total of 39 parallel I/O pins distributed between four 8-bit ports and one
7-bit port. Not all pins are bonded out in all packages. Consult the pin assignment in the
Connections
when they are not used by other on-chip peripheral systems.
Freescale Semiconductor
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NOTE:
A total of 39 general-purpose I/O pins in five ports (two pins are output only, one is input only)
High-current drivers on port B pins
Hysteresis input buffers on all inputs
Software-controlled pullups on each input pin
Eight port A pins shared with KBI1
Eight port B pins shared with SCI and TPMCH1
Eight port C pins shared with KBI2 and SPI
Seven port D pins shared with TPMCH0, ACMP, IRQ, RESET, and BKGD/MS
Eight port E pins
section for available parallel I/O pins. All of these pins are available for general-purpose I/O
Not all general-purpose I/O pins are available on all packages. To avoid extra
current drain from floating input pins, the user’s reset initialization routine in the
application program should either enable on-chip pullup devices or change the
direction of unconnected pins to outputs so the pins do not float.
MC9S08RC/RD/RE/RG
SoC Guide — MC9S08RG60/D Rev 1.10
Chapter 2 Pins and Connections
Pins and
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