Altera Reed-Solomon Compiler - Manual (Page 26)

3–8 Chapter 3: Functional Description
Signals
Reed-Solomon Compiler December 2014 Altera Corporation
User Guide
Table 3–3 shows the RS codeword parameters.
Signals
Table 3–4 shows the global signals.
Table 3–3. RS Codeword Parameters
Parameter Range
Range
(Continuous)
Description
Number of bits per
symbol
3 to 12 6 to 12 Specifies the number of bits per symbol (m).
Number of symbols per
codeword
5 to (2 m – 1) 7(R + 1) to 2 m – 1
Specifies the total number of symbols per
codeword (N).
Number of check symbols
per codeword
2 to min(128, N – 1) 4 to N/7 – 1
Specifies the number of check symbols per
codeword (R)
Field polynomial Any valid polynomial (1)
Specifies the primitive polynomial defining the
Galois field.
First root of generator
polynomial
0 to (2 m – 2)
Specifies the first root of the generator polynomial
(i
0
).
Root spacing in generator
polynomial
Any valid root space (1)
Specifies the minimum distance between roots in
the generator polynomial (a).
Notes to Table 3–3 :
(1) IP Toolbench allows you to select only legal values. For m > 8, not all legal values of the field polynomials and rootspace are present in IP
Toolbench. If you cannot find your intended field polynomial or rootspace in the IP Toolbench list, contact Altera MySupport.
Table 3–4. Global Signals
Name Description
clk clk is the main system clock. The whole MegaCore function operates on the rising edge of clk.
reset
Reset. The entire decoder is asynchronously reset when reset is asserted high. The reset signal resets the
entire system. The reset signal must be de-asserted synchronously with respect to the rising edge of clk.