From 951328a69dada02d8f3b79bd5b6c1fcb09853d69 Mon Sep 17 00:00:00 2001
From: Eric Kooistra <kooistra@astron.nl>
Date: Wed, 2 Nov 2022 16:16:39 +0100
Subject: [PATCH] Clarified FFT output width.

---
 libraries/dsp/fft/src/vhdl/fft_pkg.vhd | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libraries/dsp/fft/src/vhdl/fft_pkg.vhd b/libraries/dsp/fft/src/vhdl/fft_pkg.vhd
index 4f9f25c459..0bc0660dc2 100644
--- a/libraries/dsp/fft/src/vhdl/fft_pkg.vhd
+++ b/libraries/dsp/fft/src/vhdl/fft_pkg.vhd
@@ -70,8 +70,12 @@ package fft_pkg is
   -- Check consistancy of the FFT parameters
   function fft_r2_parameter_asserts(g_fft : t_fft) return boolean;  -- the return value is void, because always true or abort due to failure
 
-  -- FFT input and output widths
+  -- FFT input width
   function func_fft_in_scale_w(g_fft : t_fft) return natural;
+
+  -- FFT output width
+  --                 Removed MSbits     Quantized data    Rounded LSbits
+  --   c_raw_dat_w = c_fft.out_gain_w + c_fft.out_dat_w + c_raw_fraction_w
   function func_fft_raw_dat_w(g_fft : t_fft) return natural;
   function func_fft_raw_fraction_w(g_fft : t_fft) return natural;
 
-- 
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