MC9S08RC8 Datasheet, PDF (25/234 Pages) Freescale Semiconductor, Inc – Microcontrollers

Pins and Connections
Table 2-1. Pin Sharing References
Port Pins
Alternate
Function
Reference⁽¹⁾
PTA7–PTA0
KBI1P7–KBI1P0 Chapter 9, “Keyboard Interrupt (S08KBIV1)”
PTB7
TPM1CH1
Chapter 10, “Timer/PWM Module (S08TPMV1)”
PTB6–PTB2
—
Chapter 6, “Parallel Input/Output”
PTB1
PTB0
RxD1
TxD1
Chapter 11, “Serial Communications Interface (S08SCIV1)”
PTC7
PTC6
PTC5
PTC4
SS1
SPSCK1
MISO1
MOSI1
Chapter 13, “Serial Peripheral Interface (S08SPIV3)”
PTC3–PTC0 KBI2P3–KBI2P0 Chapter 9, “Keyboard Interrupt (S08KBIV1)”
PTD6
TPM1CH0
Chapter 10, “Timer/PWM Module (S08TPMV1)”
PTD5
PTD4
ACMP1+
ACMP1–
Chapter 14, “Analog Comparator (S08ACMPV1)”
PTD2
IRQ
Chapter 5, “Resets, Interrupts, and System Configuration”
PTD1
RESET
PTD0
BKGD/MS
PTE7–PTE0
—
Chapter 6, “Parallel Input/Output”
1. See this chapter for information about modules that share these pins.
When an on-chip peripheral system is controlling a pin, data direction control bits still determine what is
read from port data registers even though the peripheral module controls the pin direction by controlling
the enable for the pin’s output buffer. See the Chapter 6, “Parallel Input/Output,” for more details.
Pullup enable bits for each input pin control whether on-chip pullup devices are enabled whenever the pin
is acting as an input even if it is being controlled by an on-chip peripheral module. When the PTA7–PTA4
pins are controlled by the KBI module and are configured for rising-edge/high-level sensitivity, the pullup
enable control bits enable pulldown devices rather than pullup devices. Similarly, when PTD2 is
configured as the IRQ input and is set to detect rising edges, the pullup enable control bit enables a
pulldown device rather than a pullup device.
2.3.7 Signal Properties Summary
Table 2-2 summarizes I/O pin characteristics. These characteristics are determined by the way the
common pin interfaces are hardwired to internal circuits.
MC9S08RC/RD/RE/RG Data Sheet, Rev. 1.11
Freescale Semiconductor
25