Peripherals; Gpio Functionality; Hi08 - Motorola DSP56303 User Manual

Peripherals

1.8 Peripherals
In addition to the core features, the DSP56303 provides the following peripherals:
As many as 34 user-configurable GPIO signals
HI08 to external hosts
Dual ESSI
SCI
Triple timer module
Memory switch mode
Four external interrupt/mode control lines
1.8.1

GPIO Functionality

The GPIO port consists of up to 34 programmable signals, also used by the peripherals (HI08,
ESSI, SCI, and timer). There are no dedicated GPIO signals. After a reset, the signals are
automatically configured as GPIO. Three memory-mapped registers per peripheral control
GPIO functionality. Programming techniques for these registers to control GPIO functionality
are detailed in Chapter 5, Programming the Peripherals.
1.8.2

HI08

The HI08 is a byte-wide, full-duplex, double-buffered parallel port that can connect directly
to the data bus of a host processor. The HI08 supports a variety of buses and provides
connection with a number of industry-standard DSPs, microcomputers, and microprocessors
without requiring any additional logic. The DSP core treats the HI08 as a memory-mapped
peripheral occupying eight 24-bit words in data memory space. The DSP can use the HI08 as
a memory-mapped peripheral, using either standard polled or interrupt programming
techniques. Separate double-buffered transmit and receive data registers allow the DSP and
host processor to transfer data efficiently at high speed. Memory mapping allows you to
program DSP core communication with the HI08 registers using standard instructions and
addressing modes.
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