
MC68HC11E Family
—
Rev. 4
Technical Data
MOTOROLA
Parallel Input/Output (I/O) Ports
133
Technical Data
—
M68HC11E Family
Section 6. Parallel Input/Output (I/O) Ports
6.1 Contents
6.2
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133
6.3
Port A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134
6.4
Port B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
6.5
Port C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
6.6
Port D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
6.7
Port E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139
6.8
Handshake Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139
6.9
Parallel I/O Control Register. . . . . . . . . . . . . . . . . . . . . . . . . .141
6.2 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
Table 6-1
for a
summary of the ports and their shared functions.
Table 6-1. Input/Output Ports
Port
Input
Pins
Output
Pins
Bidirectional
Pins
Shared Functions
Port A
3
3
2
Timer
Port B
—
8
—
High-order address
Port C
—
—
8
Low-order address and data bus
Port D
—
—
6
Serial communications interface
(SCI) and serial peripheral interface
(SPI)
Port E
8
—
—
Analog-to-digital (A/D) converter