Enhanced Synchronous Serial Interface (ESSI)
Operating Modes
MOTOROLA
DSP56305 User’s Manual
7-47
7.5.3
Operating Modes
The ESSI has three basic operating modes and several data/operation formats. These
modes can be programmed using the ESSI Control Registers. The data/operation
formats available to the ESSI are selected by setting or clearing control bits in the CRA
and CRB. These control bits are WL[2:1], MOD, SYN, FSL[1:0], FSR, FSP, CKP, and
SHFD.
7.5.3.1
Normal Mode (CRB(MOD) = 0)
Normal mode is typically used to transfer data to or from a single device. Selecting the
Normal mode is accomplished by clearing the MOD bit in the CRB. In Normal mode, the
ESSI sends or receives one data word per frame (per enabled receiver or transmitter).
The transfers are periodic.
7.5.3.2
Network Mode (CRB(MOD) = 1; CRA(DC)
≠
00000)
The ESSI’s Network mode is well-suited for using the DSP in Time Division
Multiplexing (TDM) networks, or in parallel processing networks.
In Network mode, the ESSI may be programmed for two to thirty-two time slots per
frame (always the same number for receive and transmit). A single data word may be
received or transmitted (from each enabled receiver or transmitter) during each time
slot. The duration of a receive or transmit time slot equals the time needed to shift one
word in or out of the ESSI, respectively. In other words, if the word size is 24 bits, one
time slot consists of exactly 24 ESSI clock periods (“bit times”). An edge on the receive or
transmit frame sync signal (rising or falling edge, but never both) indicates the
beginning of a new data frame.
Figure 7-21
ESSI Main Modes
AA1427
ESSI
Normal
Mode
Network
Mode
On-Demand
Mode
1
0
0
1-31
CRB
MOD
CRA
DC[4:0]
Summary of Contents for DSP56305
Page 34: ...xxxii DSP56305 User s Manual MOTOROLA ...
Page 40: ...xxxvi DSP56305 User s Manual MOTOROLA ...
Page 41: ...MOTOROLA DSP56305 User s Manual 1 1 SECTION 1 DSP56305 OVERVIEW ...
Page 58: ...1 18 DSP56305 User s Manual MOTOROLA DSP56305 Overview DSP56305 Architecture Overview ...
Page 59: ...MOTOROLA DSP56305 User s Manual 2 1 SECTION 2 SIGNAL CONNECTION DESCRIPTIONS ...
Page 98: ...2 40 DSP56305 User s Manual MOTOROLA Signal Connection Descriptions JTAG OnCE Interface ...
Page 99: ...MOTOROLA DSP56305 User s Manual 3 1 SECTION 3 MEMORY CONFIGURATION ...
Page 119: ...MOTOROLA DSP56305 User s Manual 4 1 SECTION 4 CORE CONFIGURATION ...
Page 144: ...4 26 DSP56305 User s Manual MOTOROLA Core Configuration JTAG Boundary Scan Register BSR ...
Page 145: ...MOTOROLA DSP56305 User s Manual 5 1 SECTION 5 GENERAL PURPOSE I O ...
Page 149: ...HOST INTERFACE HI32 MOTOROLA DSP56305 User s Manual 6 1 SECTION 6 HOST INTERFACE HI32 ...
Page 150: ...6 2 DSP56305 User s Manual MOTOROLA HOST INTERFACE HI32 ...
Page 259: ...MOTOROLA DSP56305 User s Manual 7 1 SECTION 7 ENHANCED SYNCHRONOUS SERIAL INTERFACE ESSI ...
Page 315: ...MOTOROLA DSP56305 User s Manual 8 1 SECTION 8 SERIAL COMMUNICATION INTERFACE SCI ...
Page 347: ...MOTOROLA DSP56305 User s Manual 9 1 SECTION 9 TIMER EVENT COUNTER ...
Page 376: ...9 30 DSP56305 User s Manual MOTOROLA Timer Event Counter Timer Modes of Operation ...
Page 377: ...MOTOROLA DSP56305 User s Manual 10 1 SECTION 10 ON CHIP EMULATION MODULE ...
Page 411: ...MOTOROLA DSP56305 User s Manual 11 1 SECTION 11 JTAG PORT ...
Page 430: ...11 20 DSP56305 User s Manual MOTOROLA JTAG Port DSP56305 Boundary Scan Register ...
Page 431: ...Filter Co Processor MOTOROLA DSP56305 User s Manual 12 1 SECTION 12 FILTER CO PROCESSOR ...
Page 471: ...VITERBI CO PROCESSOR MOTOROLA DSP56305 User s Manual 13 1 SECTION 13 VITERBI CO PROCESSOR ...
Page 522: ...13 52 DSP56305 User s Manual MOTOROLA VITERBI CO PROCESSOR References ...
Page 554: ...14 32 DSP56305 User s Manual MOTOROLA CYCLIC CODE CO PROCESSOR Configuration Examples ...
Page 555: ...MOTOROLA DSP56305 User s Manual A 1 APPENDIX A BOOTSTRAP CODE ...
Page 568: ...A 14 DSP56305 User s Manual MOTOROLA Bootstrap Code ...
Page 569: ...Equates MOTOROLA DSP56305 User s Manual B 1 APPENDIX B EQUATES ...
Page 589: ...MOTOROLA DSP56305 User s Manual C 1 APPENDIX C JTAG BSDL ...
Page 590: ...C 2 DSP56305 User s Manual MOTOROLA JTAG BSDL ...
Page 600: ...C 12 DSP56305 User s Manual MOTOROLA JTAG BSDL ...
Page 601: ...MOTOROLA DSP56305 User s Manual D 1 APPENDIX D PROGRAMMING REFERENCE ...
Page 602: ...D 2 DSP56305 User s Manual MOTOROLA PROGRAMMING REFERENCE ...
Page 661: ...Y MOTOROLA DSP56305 User s Manual Index 11 ...
Page 662: ...Y Index 12 DSP56305 User s Manual MOTOROLA ...