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DSP56305 User’s Manual
MOTOROLA
Enhanced Synchronous Serial Interface (ESSI)
Operating Modes
7.5.2
ESSI Exceptions
The ESSI can generate six different exceptions.
7.5.2.1
ESSI Exception Types
The ESSI exception types are discussed in the following paragraphs (ordered from the
highest to the lowest exception priority):
1. ESSI Receive Data with Exception Status
Occurs when the receive exception interrupt is enabled, the Receive Data Register
is full, and a receiver overrun error has occurred. This exception sets the ROE bit.
The ROE bit is cleared by first reading the SSISR and then reading RX.
2. ESSI Receive Data
Occurs when the receive interrupt is enabled, the Receive Data Register is full,
and no receive error conditions exist. Reading RX clears the pending interrupt.
This error-free interrupt can use a fast interrupt service routine for minimum
overhead.
3. ESSI Receive Last Slot Interrupt
Occurs when the ESSI is in Network mode and the last slot of the frame has
ended. This interrupt is generated regardless of the Receive Mask Register
setting. The receive last slot interrupt may be used to signal that the Receive Mask
Slot Register can be reset, the DMA channels may be reconfigured, and data
memory pointers may be reassigned. Using the receive last slot interrupt
guarantees that the previous frame was serviced with the previous setting and the
new frame will be serviced with the new setting without synchronization
problems.
Note:
The maximum time it takes to service a receive last slot interrupt should not
exceed W – 1 ESSI bits service time (where W is the word length in bits).
4. ESSI Transmit Data with Exception Status
Occurs when the transmit exception interrupt is enabled, at least one Transmit
Data Register of the enabled transmitters is empty, and a transmitter underrun
error has occurred. This exception sets the TUE bit. The TUE bit is cleared by first
reading the SSISR and then writing to all the Transmit Data Registers of the
enabled transmitters, or by writing to the TSR to clear the pending interrupt.
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 ...