14-28
DSP56305 User’s Manual
MOTOROLA
CYCLIC CODE CO-PROCESSOR
Configuration Examples
Two programming cases are considered:
14.7.1.1
Case 1 - Polynomials of degree n
≤
24
In this case the Parity Coding mode using one CFSR is used (OPM[1:0] = 10 in CCSR),
that is, only CFSRA is configured. Since the data sequence is input from the left side,
LRC is cleared. The values of the coefficients g
1
and m
1
are input into bit 23 (the most
significant bit) of CFBTA and CFFTA, respectively. Similarly, g
2
and m
2
are input into
bit 22 of CFBTA and CFFTA, respectively. The other coefficients (g
a
and m
a
) are input
into bit (24–a) of CFBTA and CFFTA, respectively. The polynomial degree, n, is input by
setting bit (24–n) of CMSKA while all other bits are cleared. The parameter, m
0
, is input
into INE0. If m
0
= 1, INE0 = 1, and if m
0
= 0, INE0 = 0. Notice that the input data to the
feedforward path is always enabled and not affected by the INE0 bit.
14.7.1.2
Case 2 - Polynomials of degree n, such that 25
≤
n
≤
48
In this case the Parity Coding mode using two concatenated CFSRs is used (OPM[1:0] =
11 in CCSR), that is, CFSRB and CFSRA are concatenated together to form one
double-length CFSR. Since the data sequence is input from the left side, the LRC bit in
CCSR is cleared. The values of the coefficients g
1
and m
1
are input into bit 23 (the most
significant bit) of CFBTB and CFFTB, respectively. Similarly, g
2
and m
2
are input into bit
22 of CFBTB and CFFTB, respectively, and so on. The twenty- fourth coefficients, g
24
and
m
24
, are input into bit 0 (the least significant bit) of CFBTB and CFFTB, respectively. The
twenty-fifth coefficients, g
25
and m
25
, are input into bit 23 (the most significant bit) of
Figure 14-9
Shortened Cyclic Code Circuit
g
1
m
1
g
2
m
2
g
n–2
m
n–2
g
n–1
m
n–1
m
0
Input Data
Bit #23 of
CFSRA if n
≤
24
Bit #23 of
CFSRB if n
≤
48
Bit #22 of
CFSRA if n
≤
24
Bit #22 of
CFSRB if n
≤
48
Bit #(25-n) of
CFSRA if n
≤
24
Bit #(49-n) of
CFSRA if n
≤
48
M(x)
G(x)
D(x)
Circuit for multiplying
D(x)
by
M(x) = m
0
+m
1
•x+m
2
•x
2
+...+m
n–1
•x
n–1
and dividing the product by
G(x) = 1+g
1
•x+g
2
•x
2
+...+g
n–1
•x
n–1
+x
n
+
+
+
+
+
AA1308
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 ...