Enhanced Synchronous Serial Interface (Essi); Essi Block Diagram - Motorola DSP56303 User Manual

Chapter 7
Enhanced Synchronous Serial Interface
(ESSI)
The ESSI provides 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. The ESSI consists of independent transmitter and receiver sections and a
common ESSI clock generator. There are two independent and identical ESSIs in the
DSP56303: ESSI0 and ESSI1. For simplicity, a single generic ESSI is described here. The
ESSI block diagram is shown in Figure 7-1. This interface is synchronous because all serial
transfers are synchronized to one clock.
Interrupts
GDB
RSMA
RSMB
TSMA
TSMB
CRA
CRB
TSR
SSISR
Clock/Frame Sync Generators and Control Logic
Figure 7-1. ESSI Block Diagram

Enhanced Synchronous Serial Interface (ESSI)

DDB
RCLK
RX SHIFT REG
RX
TCLK
TX0 SHIFT REG
TX0
TX1 SHIFT REG
TX1
TX2 SHIFT
TX2
SRD
STD
SC0
SC1
SC2
SCK
7-1