mc68hc11e0fnr2 Freescale Semiconductor, Inc, mc68hc11e0fnr2 Datasheet - Page 97

• Manufacturer Part Number: mc68hc11e0fnr2
• Description: Hc11 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Chapter 6
Parallel Input/Output (I/O) Ports
6.1 Introduction
All M68HC11 E-series MCUs have five input/output (I/O) ports and up to 38 I/O lines, depending on the
operating mode. Refer to
Port pin function is mode dependent. Do not confuse pin function with the electrical state of the pin at
reset. Port pins are either driven to a specified logic level or are configured as high-impedance inputs. I/O
pins configured as high-impedance inputs have port data that is indeterminate.
In port descriptions, an I indicates this condition. Port pins that are driven to a known logic level during
reset are shown with a value of either 1 or 0. Some control bits are unaffected by reset. Reset states for
these bits are indicated with a U.
Freescale Semiconductor
Port A
Port B
Port C
Port D
Port E
Port
Input
Pins
—
—
—
3
8
Table 6-1
Output
Pins
—
—
—
3
8
M68HC11E Family Data Sheet, Rev. 5.1
for a summary of the ports and their shared functions.
Table 6-1. Input/Output Ports
Bidirectional
Pins
—
—
2
8
6
Timer
High-order address
Low-order address and data bus
Serial communications interface (SCI)
and serial peripheral interface (SPI)
Analog-to-digital (A/D) converter
Shared Functions
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