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DSP56309UM/D MOTOROLA
Enhanced Synchronous Serial Interface (ESSI)
Operating Modes
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 can be used to signal that the receive mask slot register
can be reset, the DMA channels can be reconfigured, and data memory pointers
can be reassigned. Using the receive last slot interrupt guarantees that the
previous frame was serviced with the previous setting and the new frame is
serviced with the new setting without synchronization problems.
Note:
The maximum time it takes to service a receive last slot interrupt should not
exceed N Ð 1 ESSI bits service time (where N is the number of bits the ESSI can
transmit per time slot).
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.
5. ESSI transmit last slot interrupt:
Occurs when the ESSI is in network mode at the start of the last slot of the frame.
This exception occurs regardless of the transmit mask register setting. The
transmit last slot interrupt can be used to signal that the transmit mask slot
register can be reset, the DMA channels can be reconfigured, and data memory
pointers can be reassigned. Using the transmit last slot interrupt guarantees that
the previous frame was serviced with the previous setting, and the new frame is
serviced with the new setting without synchronization problems.
Note:
The maximum transmit last slot interrupt service time should not exceed
N Ð 1 ESSI bits service time (where N is the number of bits in a slot).
6. ESSI transmit data:
Occurs when the transmit interrupt is enabled, at least one of the enabled transmit
data registers is empty, and no transmitter error conditions exist. Writing to all
the enabled TX registers or to the TSR clears this interrupt. This error-free
interrupt can use a fast interrupt service routine for minimum overhead (if no
more than two transmitters are used).
To configure an ESSI exception, perform the following steps:
Summary of Contents for DSP56309
Page 25: ...xxii DSP56309UM D MOTOROLA Figure D 25 Port E Registers PCRE PRRE PDRE D 39 ...
Page 30: ...MOTOROLA DSP56309UM D 1 1 SECTION 1 DSP56309 OVERVIEW ...
Page 47: ...1 18 DSP56309UM D MOTOROLA DSP56309 Overview DSP56309 Architecture Overview ...
Page 48: ...MOTOROLA DSP56309UM D 2 1 SECTION 2 SIGNAL CONNECTION DESCRIPTIONS ...
Page 85: ...2 38 DSP56309UM D MOTOROLA Signal Connection Descriptions OnCE JTAG Interface ...
Page 86: ...MOTOROLA DSP56309UM D 3 1 SECTION 3 MEMORY CONFIGURATION ...
Page 104: ...MOTOROLA DSP56309UM D 4 1 SECTION 4 CORE CONFIGURATION ...
Page 124: ...MOTOROLA DSP56309UM D 5 1 SECTION 5 GENERAL PURPOSE I O ...
Page 125: ...5 2 DSP56309UM D MOTOROLA General Purpose I O 5 1 INTRODUCTION 5 3 5 2 PROGRAMMING MODEL 5 3 ...
Page 128: ...MOTOROLA DSP56309UM D 6 1 SECTION 6 HOST INTERFACE HI08 ...
Page 166: ...MOTOROLA DSP56309UM D 7 1 SECTION 7 ENHANCED SYNCHRONOUS SERIAL INTERFACE ESSI ...
Page 212: ...MOTOROLA DSP56309UM D 8 1 SECTION 8 SERIAL COMMUNICATION INTERFACE SCI ...
Page 241: ...8 30 DSP56309UM D MOTOROLA Serial Communication Interface SCI GPIO Signals and Registers ...
Page 242: ...MOTOROLA DSP56309UM D 9 1 SECTION 9 TRIPLE TIMER MODULE ...
Page 269: ...9 28 DSP56309UM D MOTOROLA Triple Timer Module Timer Operational Modes ...
Page 270: ...MOTOROLA DSP56309UM D 10 1 SECTION 10 ON CHIP EMULATION MODULE ...
Page 302: ...MOTOROLA DSP56309UM D 11 1 SECTION 11 JTAG PORT ...
Page 369: ...C 22 DSP56309UM D MOTOROLA DSP56309 BSDL Listing ...
Page 370: ...MOTOROLA DSP56309UM D D 1 APPENDIX D PROGRAMMING REFERENCE ...
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