MC9S12KT256 Datasheet, PDF (38/594 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 1 MC9S12KT256 Device Overview (MC9S12KT256V1)
1.2.2.52 PS3 / TXD1 — Port S I/O Pin 3
PS3 is a general purpose input or output pin. It can be configured as the transmit pin TXD of Serial
Communication Interface 1 (SCI1).
1.2.2.53 PS2 / RXD1 — Port S I/O Pin 2
PS2 is a general purpose input or output pin. It can be configured as the receive pin RXD of Serial
Communication Interface 1 (SCI1).
1.2.2.54 PS1 / TXD0 — Port S I/O Pin 1
PS1 is a general purpose input or output pin. It can be configured as the transmit pin TXD of Serial
Communication Interface 0 (SCI0).
1.2.2.55 PS0 / RXD0 — Port S I/O Pin 0
PS0 is a general purpose input or output pin. It can be configured as the receive pin RXD of Serial
Communication Interface 0 (SCI0).
1.2.2.56 PT[7:0] / IOC[7:0] — Port T I/O Pins [7:0]
PT7-PT0 are general purpose input or output pins. They can be configured as input capture or output
compare pins IOC7-IOC0 of the Timer (TIM).
1.2.3 Power Supply Pins
MC9S12KT256 power and ground pins are described below.
NOTE
All VSS pins must be connected together in the application.
1.2.3.1 VDDX,VSSX — Power Supply Pins for I/O Drivers
External power and ground for I/O drivers. Because fast signal transitions place high, short-duration
current demands on the power supply, use bypass capacitors with high-frequency characteristics and place
them as close to the MCU as possible. Bypass requirements depend on how heavily the MCU pins are
loaded.
1.2.3.2 VDDR, VSSR — Power Supply Pins for I/O Drivers & for Internal Voltage
Regulator
External power and ground for I/O drivers and input to the internal voltage regulator. Because fast signal
transitions place high, short-duration current demands on the power supply, use bypass capacitors with
high-frequency characteristics and place them as close to the MCU as possible. Bypass requirements
depend on how heavily the MCU pins are loaded.
MC9S12KT256 Data Sheet, Rev. 1.15
38
Freescale Semiconductor