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6/17/03
21-1
Chapter 21
General Purpose Input/Output
The General Purpose Input/Output (GPIO) is a slave module that connects to the APB.
The SoCs use five GPIO modules. Each module has two 8-bit ports, designated A through
J, and provides 76 bits of programmable input/output. Figure 21-1 shows a block diagram
of the GPIO.
NOTE: Users may want to consult the truth tables in Chapter 24 while reading about the I/O system.
Figure 21-1. GPIO Block Diagram
LH754xx-29
PORT A
REGISTERS
PORT A
PORT B
PORT C
PORT D
PORT E
PORT F
PORT G
PORT H
PORT I
PORT J
PORT B
REGISTERS
PORT C
REGISTERS
PORT D
REGISTERS
APB
INTERFACE
PORT E
REGISTERS
PORT F
REGISTERS
PORT G
REGISTERS
PORT H
REGISTERS
PORT I
REGISTERS
PORT J
REGISTERS
ADVANCED
PERIPHERAL
BUS (APB)