Introduction; Gpio Programming Model; Figure 7-1 Gpio Control/Data Register - Motorola DSP56012 User Manual

7.1

INTRODUCTION

The General Purpose Input/Output (GPIO) pins are used for control and handshake
functions between the DSP and external circuitry. The GPIO port has eight I/O pins
(GPIO0–GPIO7) that are controlled through a memory-mapped register. Each GPIO
pin may be individually programmed as an output or as an input.
7.2

GPIO PROGRAMMING MODEL

The GPIO pins are controlled through the GPIO control/data Register (GPIOR),
which is illustrated in Figure 7-1. The register is described in the following
paragraphs.
7
GD7
15
GDD7
23
GC7
7.3 GPIO REGISTER (GPIOR)
The GPIO Register (GPIOR) is a 24-bit read/write control/data register used to
operate and configure the GPIO pins. The control bits in the GPIOR select the
direction of data transfer for each pin, whereas the data bits in the GPIOR are used to
read from or write to the GPIO pins. Hardware reset and software reset clear all the
bits in GPIOR. The GPIOR bits are described in the following paragraphs.
MOTOROLA
6 5 4
GD6 GD5 GD4
14 13 12
GDD6 GDD5 GDD4 GDD3
22 21 20
GC6 GC5 GC4

Figure 7-1 GPIO Control/Data Register

DSP56012 User's Manual
3 2 1
GD2 GD1 GD0
GD3
11 10 9
GDD1 GDD0
GDD2
19 18 17
GC3 GC2 GC1 GC0
Introduction
0
GPIOR
X:$FFF7
8
16
AA0441.11
GPIO
7-3