Serial Communication Interface (SCI)
GPIO Signals and Registers
MOTOROLA
DSP56305 User’s Manual
8-29
8.4.5
SCI Exceptions
The SCI can cause five different exceptions in the DSP. These exceptions are as follows
(ordered from the highest to the lowest priority):
1. SCI Receive Data with Exception Status is caused when the Receive Data Register
is full and has a receive error (parity, framing, or overrun). Clearing the pending
interrupt is done by reading the SSR, followed by reading SRX. A long interrupt
service routine should be used to handle the error condition. This interrupt is
enabled by SCR Bit 16 (REIE).
2. SCI Receive Data is caused when the Receive Data Register is full. Reading SRX
clears the pending interrupt. This error-free interrupt can use a fast interrupt
service routine for minimum overhead. This interrupt is enabled by SCR Bit 11
(RIE).
3. SCI Transmit Data is caused when the Transmit Data Register is empty. Writing
STX clears the pending interrupt. This error-free interrupt can use a fast interrupt
service routine for minimum overhead. This interrupt is enabled by SCR Bit 12
(TIE).
4. SCI Idle Line is caused when the receive line enters the idle state (when there
have been ten or eleven bits of 1s transmitted). This interrupt is latched and then
automatically reset when the interrupt is accepted. This interrupt is enabled by
SCR Bit 10 (ILIE).
5. SCI Timer is caused when the baud rate counter reaches zero. This interrupt is
automatically reset when the interrupt is accepted. This interrupt is enabled by
SCR Bit 13 (TMIE).
8.5
GPIO SIGNALS AND REGISTERS
The GPIO functionality of port SCI is controlled by three registers: Port E Control
Register (PCRE), Port E Direction Register (PRRE) and Port E Data Register (PDRE).
8.5.1
Port E Control Register (PCRE)
The read/write 24-bit PCRE controls the functionality of SCI GPIO signals. Each of
PC[2:0] bits controls the functionality of the corresponding port signal. When a PC[i] bit
is set, the corresponding port signal is configured as a SCI signal. When a PC[i] bit is
cleared, the corresponding port signal is configured as a GPIO signal.
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 ...
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