Altera Reed-Solomon Compiler - Manual (Page 28)

3–10 Chapter 3: Functional Description
Throughput Calculator
Reed-Solomon Compiler December 2014 Altera Corporation
User Guide
Table 3–7 shows the configuration signals.
Table 3–8 shows the status signals (decoder only).
Throughput Calculator
The IP Toolbench throughput calculator (decoder only) uses the following equation:
Throughput in megasymbols per second = N × frequency (MHz)/N
C
For Mbps, multiply by m, the number of bits per symbol.
rsout data Output
The rsout signal contains decoded output when source_val is asserted. The
corrected symbols are in the same order that they were entered.
rserr data Output
Error correction value (decoder only, optional). Refer to “Error Symbol Output” on
page 3–5 .
Table 3–6. Avalon-ST Source Interface (Part 2 of 2)
Name
Avalon-ST
Type
Direction Description
Table 3–7. Configuration Signals
Name Description
bypass
A one-bit signal that sets if the codewords are bypassed or not (decoder only). The decoder continuously
samples bypass.
numcheck
Sets the variable number of check symbols up to a maximum value set by the parameter R (variable option
only). The decoder samples numcheck only when sink_sop is asserted.
numn
Variable value of N. Can be any value from the minimum allowable value of N up to the selected value of N
(variable and erasures-supporting option only). The decoder samples numn only when sink_sop is
asserted.
Table 3–8. Status Signals
Name Description
decfail Indicates non-correctable codeword. Valid when source_sop is asserted. Avalon-ST type err.
num_err_sym Number of symbols errors. Valid when source_sop is asserted; invalid when decfail is asserted.
num_err_bit
Number of bits errors corrected in the codeword. Valid when source_sop is asserted; invalid when
decfail
is asserted. Connected only when the Bit error (Full count) option is turned on. Refer to “RS
Decoder” on page 3–4 .
num_err_bit0
Number of bit errors for the corrections from bit 1 to bit 0. The latest is the correct bit. Valid when
sop_source
is asserted; invalid when decfail is asserted. The decoder presents these values at the
next source_sop assertion (at the next codeword). Connected only when the Bit error (Split count)
option is turned on.
num_err_bit1
Number of bit errors for the corrections from bit 0 to bit 1. The latest is the correct bit. Valid when
sop_source
is asserted; invalid when decfail is asserted. The decoder presents these values at the
next source_sop assertion (at the next codeword). Connected only when the Bit error (Split count)
option is turned on.