VITERBI CO-PROCESSOR
Programming Model
MOTOROLA
DSP56305 User’s Manual
13-29
13.5.11.1
Window Start Location (WSTR[7:0])—VWES Bits 7–0
The Window Start Location (WSTR[7:0]) bits are used to specify the start location of the
WED window in the data block. The value assigned to WSTR[7:0] should be (N–L–1),
where N is the number of decoded bits in the data block and L is the start bit location for
WED computation.
13.5.11.2
Window Length (WLEN[7:0])—VWES Bits 15–8
The Window Length (WLEN[7:0]) bits specify the length of the WED window. The value
assigned to WLEN[7:0] should be the window bit-length minus one.
For example, assuming a GSM half rate speech data block (TCH/HS) of 104 decoded
bits, numbered 1, 2, 3,..., 104, in which the WED window starts at bit 75, and the WED
window length is 25 bits, the following parameters need to be input:
VCNT = block_size – 1 = 104 – 1 = 103 = $67
WSTR = block_size – start_bit – 1 = 104 – 75 – 1 = 28 = $1C
WLEN = window_length – 1 = 25 – 1 = 24 = $18
13.5.12
Viterbi WED Data Register (VWED)
The VWED is a 16-bit read-only data register used for reading the WED value. The
calculation of the WED is enabled by setting WEDE (VCRB Bit 6). The value provided is
the minimal difference in path metrics of all ACS decisions along the survivor path
within the defined window. The window is defined using the VWES register. The
VWED is cleared when the decoding mode is enabled. The WED function is performed
during decoding only.
13.5.13
Viterbi Memory Access Register (VMEM)
The Viterbi Memory Access Register (VMEM) is a 24-bit read/write data register, used
in Memory Access mode to access the VCOP RAM modules (excluding Output Buffer
and Trellis RAM). When accessing 16-bit word data RAM, the data occupies the sixteen
most significant bits of VMEM, zero padded at the [7:0] bits. For the Metric RAM access,
the data bits occupies bits [21:0] of VMEM, zero extended to bits [23:22]. The data
address is defined by the VBER, see Table 13-7 on page 30. WED accuracy, (as given in
the VWED register), is plus or minus one of the correct minimal difference decision
along the surviving path.
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 ...