From 49e910957ca26ba9d7d8e70715a541b0a864dfe0 Mon Sep 17 00:00:00 2001
From: Mike Field <hamster@snap.net.nz>
Date: Sun, 9 Aug 2015 16:37:51 +1200
Subject: [PATCH] Fix up all known issues with interlaced video modes.

Guidelines are now correct. Audio meters are the correct sice.
---
 Artix-7-HDMI-processing.xpr | 13 +++++----
 README.txt                  | 10 ++-----
 src/audio_meters.vhd        | 16 ++++++++---
 src/guidelines.vhd          |  9 +++++-
 src/hdmi_design.vhd         | 55 ++++++++++++++++++++-----------------
 5 files changed, 59 insertions(+), 44 deletions(-)

diff --git a/Artix-7-HDMI-processing.xpr b/Artix-7-HDMI-processing.xpr
index 01d08fe..8174774 100644
--- a/Artix-7-HDMI-processing.xpr
+++ b/Artix-7-HDMI-processing.xpr
@@ -121,12 +121,6 @@
           <Attr Name="UsedIn" Val="simulation"/>
         </FileInfo>
       </File>
-      <File Path="$PPRDIR/src/symbol_dump.vhd">
-        <FileInfo>
-          <Attr Name="UsedIn" Val="synthesis"/>
-          <Attr Name="UsedIn" Val="simulation"/>
-        </FileInfo>
-      </File>
       <File Path="$PPRDIR/src/pixel_processing.vhd">
         <FileInfo>
           <Attr Name="UsedIn" Val="synthesis"/>
@@ -145,6 +139,13 @@
           <Attr Name="UsedIn" Val="simulation"/>
         </FileInfo>
       </File>
+      <File Path="$PPRDIR/src/symbol_dump.vhd">
+        <FileInfo>
+          <Attr Name="AutoDisabled" Val="1"/>
+          <Attr Name="UsedIn" Val="synthesis"/>
+          <Attr Name="UsedIn" Val="simulation"/>
+        </FileInfo>
+      </File>
       <Config>
         <Option Name="DesignMode" Val="RTL"/>
         <Option Name="TopModule" Val="hdmi_design"/>
diff --git a/README.txt b/README.txt
index 51ec522..247ba35 100644
--- a/README.txt
+++ b/README.txt
@@ -44,16 +44,10 @@ Known issues:
  - Does not adjust PLL settings for input clock, so the PLL is run slightly out
    of spec.
 
- - Image may re-sync after a few seconds if it receives errors.
-
- - The audio meters are drawn twice as tall in interlaced modes
-
- - A false VSYNC pulse is causing the meters to be displayed more than once when
-   some content is shown. Very weird, but I want to leave this in for now so I can
-   find the root cause.
+ - Image may re-sync once after a few seconds if symbol errors are seen.
 
  - There are timings errors, as generating 148.5MHz HDMI using the Artix-7 chip
-   is actualy out of spec. Expect seven failing paths and about 20ns of negative 
+   is actually out of spec. Expect seven failing paths and about 20ns of negative 
    slack.
 
 ------------------------------------------------------------------------------------
diff --git a/src/audio_meters.vhd b/src/audio_meters.vhd
index c935057..173f134 100644
--- a/src/audio_meters.vhd
+++ b/src/audio_meters.vhd
@@ -149,7 +149,7 @@ level_proc: process(clk)
                 end if;
             end if;
 
-            -- Drop the levels once each frame
+            -- Signal to reduce (drop' the levels of the meters once each frame (of field for interlaced sources
             if last_vsync = '0'  and in_vsync = '1' then
                 pending_drop <= '1';
                 drop_index <= (others => '1');
@@ -242,13 +242,21 @@ video_proc: process(clk)
 
             -- The end of active video is used to increment the line count           
             if last_blank = '0' and in_blank = '1' then
-                line_count <= line_count + 1;
+                if is_interlaced = '1' then
+                    line_count <= line_count + 2;
+                else
+                    line_count <= line_count + 1;
+                end if;
                 col_count <= (others => '0');
             end if; 
                         
             -- Reset the line count on falling vsync
-            if last_vsync = '0'  and in_vsync = '1' then
-                line_count <= (others => '0');
+            if last_vsync = '1'  and in_vsync = '0' then
+                if is_interlaced = '1' and is_second_field = '1' then
+                    line_count <= (0 => '1', others => '0');
+                else
+                    line_count <= (others => '0');
+                end if;
             end if;
             -- remember the hsync and vsync values
             last_vsync <= in_vsync;
diff --git a/src/guidelines.vhd b/src/guidelines.vhd
index 710ad4e..d477f47 100644
--- a/src/guidelines.vhd
+++ b/src/guidelines.vhd
@@ -91,7 +91,7 @@ process(clk)
             out_red    <= in_red;
             out_green  <= in_green;
             out_blue   <= in_blue;
-            
+
             if enable_feature = '1' then
                 if h_size = 1280 then
                     if hcount = 426 or hcount = 854 then
@@ -132,19 +132,26 @@ process(clk)
                 end if;
             end if;
                             
+            -------------------------------------------------------------
             -- Count the number of lines in a frame (not field!!!)
+            -------------------------------------------------------------
             if last_blank = '0' and in_blank = '1' then
                 vcount <= vcount + 1;
             end if;
+            
+            -------------------------------------------------------------
             -- Use the falling edge of VSYNC to to capture the number of 
             -- lines on the screen, as the rising edge is where the 
             -- interaced field is detected and can be a bit unstable.
+            -------------------------------------------------------------
             if in_vsync = '0' and last_vsync = '1' and is_second_field = '0'then
                 vcount <= (others => '0');
                 v_size <= vcount;
             end if;
 
+            -------------------------------------------------------------
             -- Count the width of the frame
+            -------------------------------------------------------------
             if in_blank = '1' then
                 if hcount /= 0 then
                     h_size <= hcount;
diff --git a/src/hdmi_design.vhd b/src/hdmi_design.vhd
index e4470de..47cf2e3 100644
--- a/src/hdmi_design.vhd
+++ b/src/hdmi_design.vhd
@@ -272,12 +272,14 @@ i_hdmi_io: hdmi_io port map (
         -------------------------------
         -- VGA data recovered from HDMI
         -------------------------------
-        in_blank => in_blank,
-        in_hsync => in_hsync,
-        in_vsync => in_vsync,
-        in_red   => in_red,
-        in_green => in_green,
-        in_blue  => in_blue,
+        in_blank        => in_blank,
+        in_hsync        => in_hsync,
+        in_vsync        => in_vsync,
+        in_red          => in_red,
+        in_green        => in_green,
+        in_blue         => in_blue,
+        is_interlaced   => is_interlaced,
+        is_second_field => is_second_field,
 
         -----------------------------------
         -- For symbol dump or retransmit
@@ -308,17 +310,17 @@ i_processing: pixel_processing Port map (
         ------------------
         -- Incoming pixels
         ------------------
-        in_blank => in_blank,
-        in_hsync => in_hsync,
-        in_vsync => in_vsync,
-        in_red   => in_red,
-        in_green => in_green,
-        in_blue  => in_blue,    
-        is_interlaced => is_interlaced,
+        in_blank        => in_blank,
+        in_hsync        => in_hsync,
+        in_vsync        => in_vsync,
+        in_red          => in_red,
+        in_green        => in_green,
+        in_blue         => in_blue,    
+        is_interlaced   => is_interlaced,
         is_second_field => is_second_field,
-        audio_channel => audio_channel,
-        audio_de      => audio_de,
-        audio_sample  => audio_sample,
+        audio_channel   => audio_channel,
+        audio_de        => audio_de,
+        audio_sample    => audio_sample,
         -------------------
         -- Processed pixels
         -------------------
@@ -330,13 +332,16 @@ i_processing: pixel_processing Port map (
         out_blue  => out_blue
     );
 
-i_symbol_dump: symbol_dump port map (
-            clk         => pixel_clk,
-            clk100      => clk100,
-            symbol_sync => symbol_sync,
-            symbol_ch0  => symbol_ch0,
-            symbol_ch1  => symbol_ch1,
-            symbol_ch2  => symbol_ch2, 
-            rs232_tx    => rs232_tx);        
-
+    -- Swap to this if you want to capture the HDMI symbols
+    -- and send them up the RS232 port
+    rs232_tx <= '1';
+--i_symbol_dump: symbol_dump port map (
+--            clk         => pixel_clk,
+--            clk100      => clk100,
+--            symbol_sync => symbol_sync,
+--            symbol_ch0  => symbol_ch0,
+--            symbol_ch1  => symbol_ch1,
+--            symbol_ch2  => symbol_ch2, 
+--            rs232_tx    => rs232_tx);        
+    
 end Behavioral;
\ No newline at end of file