Enhanced Synchronous Serial Interface; Essi0; Table 2-12 Enhanced Synchronous Serial Interface 0 (Essi0) - Motorola DSP56309 User Manual

Signal/Connection Descriptions

Enhanced Synchronous Serial Interface

2.9

ENHANCED SYNCHRONOUS SERIAL INTERFACE

Two synchronous serial interfaces (ESSI0 and ESSI1) provide a full-duplex serial port for
serial communication with a variety of serial devices, including one or more
industry-standard codecs, other DSPs, microprocessors, and peripherals which
implement the Motorola SPI.
2.9.1

ESSI0

The ESSI0 signal descriptions for the DSP56309 are listed in Table 2-12.

Table 2-12 Enhanced Synchronous Serial Interface 0 (ESSI0)

Signal
Name
SC00 Input or
Output
PC0
2-24
State
Type During
Reset
Input
DSP56309UM/D
Signal Description
Serial Control 0ÑThe function of SC00 is
determined by the selection of either
synchronous or asynchronous mode. For
asynchronous mode, this signal is used for
the receive clock I/O (Schmitt-trigger input).
For synchronous mode, this signal is used
either for Transmitter 1 output or for Serial
I/O Flag 0.
This signal is driven by a weak keeper after
reset.
Port C 0ÑThe default configuration
following reset is GPIO input PC0. When this
port is configured as PC0, signal direction is
controlled through the Port C direction
register (PRR0). The signal can be configured
as ESSI signal SC00 through the Port C
control register (PCR0).
MOTOROLA