MC68HC908AS32A Datasheet, PDF (25/280 Pages) Freescale Semiconductor, Inc – Microcontrollers

Pin Assignments
1.4.7 Analog Ground Pin (V_SSA/V_REFL)
The V_SSA/V_REFL pin provides both the analog ground connection and the reference low voltage for the
ADC as well as the ground connection for the CGM. See Chapter 3 Analog-to-Digital Converter (ADC)
and Chapter 5 Clock Generator Module (CGM) for more information.
1.4.8 ADC Reference High Voltage Pin (V_REFH)
V_REFH provides the reference high voltage for the ADC. See Chapter 3 Analog-to-Digital Converter (ADC)
for more information.
1.4.9 Port A Input/Output (I/O) Pins (PTA7–PTA0)
PTA7–PTA0 are general-purpose bidirectional input/output (I/O) port pins. See Chapter 13 Input/Output
Ports for more information.
1.4.10 Port B I/O Pins (PTB7/ATD7–PTB0/ATD0)
Port B is an 8-bit special function port that shares all eight pins with the ADC. See Chapter 3
Analog-to-Digital Converter (ADC) and Chapter 13 Input/Output Ports for more information.
1.4.11 Port C I/O Pins (PTC4–PTC0)
PTC4–PTC3 and PTC1–PTC0 are general-purpose bidirectional I/O port pins. PTC2/MCLK is a special
function port that shares its pin with the system clock which has a frequency equivalent to the system
clock. See Chapter 13 Input/Output Ports for more information.
1.4.12 Port D I/O Pins (PTD6–PTD0/ATD8)
Port D is an 7-bit special-function port that shares seven of its pins with the ADC and one of its pins with
the TIM. See Chapter 17 Timer Interface Module (TIM), Chapter 3 Analog-to-Digital Converter (ADC), and
Chapter 13 Input/Output Ports for more information.
1.4.13 Port E I/O Pins (PTE7/SPSCK–PTE0/TxD)
Port E is an 8-bit special function port that shares two of its pins with the TIM, four of its pins with the SPI,
and two of its pins with the SCI. See Chapter 14 Serial Communications Interface (SCI), Chapter 16 Serial
Peripheral Interface (SPI), Chapter 17 Timer Interface Module (TIM), and Chapter 13 Input/Output Ports
for more information.
1.4.14 Port F I/O Pins (PTF3–PTF0/TCH2)
Port F is a 4-bit special function port that shares four of its pins with the TIM. See Chapter 17 Timer
Interface Module (TIM) and Chapter 13 Input/Output Ports for more information.
1.4.15 BDLC Transmit Pin (BDTxD)
This pin is the digital output from the BDLC module (BDTxD). See Chapter 19 Electrical Specifications for
more information.
MC68HC908AS32A Data Sheet, Rev. 2.0
Freescale Semiconductor
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