DSP56303 datasheet(23/292 Pages) FREESCALE

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Peripherals

DSP56303 User’s Manual, Rev. 2

Freescale Semiconductor

1-13

Network mode operation with as many as 32 time slots

Programmable word length (8, 12, or 16 bits)

Program options for frame synchronization and clock generation

One receiver and three transmitters per ESSI

1.9.4 SCI

The SCI provides a full-duplex port for serial communication with other DSPs, microprocessors,

or peripherals such as modems. The SCI interfaces without additional logic to peripherals that

use TTL-level signals. With a small amount of additional logic, the SCI can connect to peripheral

interfaces that have non-TTL level signals, such as the RS-232C, RS-422, etc. This interface uses

three dedicated signals: transmit data, receive data, and SCI serial clock. It supports

industry-standard asynchronous bit rates and protocols, as well as high-speed synchronous data

transmission (up to 12.5 Mbps for a 100 MHz clock). SCI asynchronous protocols include a

multidrop mode for master/slave operation with wakeup on idle line and wakeup on address bit

capability. This mode allows the DSP56303 to share a single serial line efficiently with other

peripherals.

Separate SCI transmit and receive sections can operate asynchronously with respect to each

other. A programmable baud-rate generator provides the transmit and receive clocks. An enable

vector and an interrupt vector allow the baud-rate generator to function as a general-purpose

timer when the SCI is not using it or when the interrupt timing is the same as that used by the

SCI.

1.9.5 Timer Module

The triple timer module is composed of a common 21-bit prescaler and three independent and

identical general-purpose 24-bit timer/event counters, each with its own memory-mapped

A single signal that can function as a GPIO signal or as a timer signal

Uses internal or external clocking and can interrupt the DSP after a specified number of

events (clocks) or signal an external device after counting internal events

Connection to the external world through one bidirectional signal. When this signal is

configured as an input, the timer functions as an external event counter or measures

external pulse width/signal period. When the signal is used as an output, the timer

functions as either a timer, a watchdog, or a pulse width modulator.

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