add signus signal

01-WaveformGenerator/WaveformGenerator/hdl/lowpass_studentVersion.vhd

@@ -1,4 +1,17 @@
 ARCHITECTURE studentVersion OF lowpass IS
+
+  signal accumulator: unsigned((signalBitNb-1)+shiftBitNb downto 0);
+
 BEGIN
-  lowpassOut <= (others => '0');
+
+  process(clock)
+  begin
+    if reset = '1' then
+      accumulator <= (others => '0');
+    elsif rising_edge(clock) then
+      accumulator <= accumulator + resize(lowpassIn,signalBitNb+shiftBitNb) - shift_right(accumulator, shiftBitNb);
+    end if;
+  end process;
+
+  lowpassOut <= resize(shift_right(accumulator, shiftBitNb), signalBitNb);
 END ARCHITECTURE studentVersion;