Altera FFT MegaCore Function User Manual
Page 41
Signal Name
Directio
n
Avalon-ST Type
Size
Description
source_eop
Output
endofpacket
1
Marks the end of the outgoing FFT
frame. Only valid when
source_valid
is asserted.
source_
error
Output
error
2
Indicates an error has occurred either
in an upstream module or within the
FFT module (logical
OR
of
sink_error
with errors generated in the FFT).
source_exp
Output
data
6
Streaming, burst, and buffered burst
FFTs only. Signed block exponent:
Accounts for scaling of internal signal
values during FFT computation.
source_
imag
Output
data
(data
precision
width +
growth)
(1)
Imaginary output data. For burst,
buffered burst, streaming, and variable
streaming floating point FFTs, the
output data width is equal to the input
data width. For variable streaming
fixed point FFTs, the size of the output
data is dependent on the number of
stages defined for the FFT and is 2 bits
per radix 2
2
stage.
source_
ready
Input
ready
1
Asserted by the downstream module if
it is able to accept data.
source_
real
Output
data
(data
precision
width +
growth)
Real output data. For burst, buffered
burst, streaming, and variable
streaming floating point FFTs, the
output data width is equal to the input
data width. For variable streaming
fixed point FFTs, the size of the output
data is dependent on the number of
stages defined for the FFT and is 2 bits
per radix 2
2
stage. Variable streaming
fixed point FFT only. Growth is log
2
(N)
+1.
source_sop
Output
startofpacket
1
Marks the start of the outgoing FFT
frame. Only valid when
source_valid
is asserted.
source_
valid
Output
valid
1
Asserted by the FFT when there is valid
data to output.
source_
data
Output
data
Variable
In Qsys systems, this Avalon-ST-
compliant data bus includes all the
Avalon-ST output data signals.
Related Information
•
•
3-18
FFT IP Core Avalon-ST Signals
UG-FFT
2014.12.15
Altera Corporation
FFT IP Core Functional Description