From ea6b3418dee47b4e97aba80041967ee40efa8bbc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Klemens=20Sch=C3=B6lhorn?= <klemens@schoelhorn.eu>
Date: Thu, 23 Nov 2017 02:12:25 +0100
Subject: [PATCH] Add the actual init sequence for clocks <= 65 MHz

---
 init_ch7301c.ucf |  9 ---------
 init_ch7301c.vhd | 50 ++++++++++++++++++++++++++++++++++--------------
 2 files changed, 36 insertions(+), 23 deletions(-)

diff --git a/init_ch7301c.ucf b/init_ch7301c.ucf
index 1a1eb2f..63aeefa 100644
--- a/init_ch7301c.ucf
+++ b/init_ch7301c.ucf
@@ -6,15 +6,6 @@ NET "i2c_scl" LOC = U27;
 NET "i2c_sda" LOC = T29;
 NET "dvi_reset" LOC = AK6;
 
-NET "dip(0)" LOC = AC24;
-NET "dip(1)" LOC = AC25;
-NET "dip(2)" LOC = AE26;
-NET "dip(3)" LOC = AE27;
-NET "dip(4)" LOC = AF26;
-NET "dip(5)" LOC = AF25;
-NET "dip(6)" LOC = AG27;
-NET "dip(7)" LOC = U25;
-
 NET "led(0)" LOC = H18;
 NET "led(1)" LOC = L18;
 NET "led(2)" LOC = G15;
diff --git a/init_ch7301c.vhd b/init_ch7301c.vhd
index 3e53b84..dbe9e4e 100644
--- a/init_ch7301c.vhd
+++ b/init_ch7301c.vhd
@@ -23,7 +23,6 @@ entity init_ch7301c is
         -- tmp
         dvi_reset: out std_logic;
         led: out std_logic_vector(7 downto 0);
-        dip: in std_logic_vector(7 downto 0);
         led_n: out std_logic;
         led_s: out std_logic;
         led_c: out std_logic
@@ -67,7 +66,7 @@ begin
         -- ch7301c needs some time (>2µs) to init its i2c port after reset
         constant max_delay: integer := input_clk / 200_000; -- 5µs
         variable delay: integer range 0 to max_delay := 0;
-        variable busy_count: integer range 0 to 3 := 0;
+        variable busy_count: integer range 0 to 10 := 0;
     begin
         if reset = '1' then
             delay := 0;
@@ -101,25 +100,48 @@ begin
 
                 case busy_count is
                     when 0 =>
-                        -- no command accepted yet, insert first one
+                        -- start configure sequence
                         i2c_execute <= '1';
                         i2c_write <= '1';
                         i2c_address <= address;
-                        i2c_data_in <= dip;
+                        -- select register PM (power management)
+                        i2c_data_in <= x"49";
                     when 1 =>
-                        -- submit read command
-                        i2c_write <= '0';
+                        -- enable clock pll, dvi encoder and transmitter
+                        i2c_data_in <= x"C0";
+
                     when 2 =>
-                        -- read submitted, wait for results, no more commands
-                        i2c_execute <= '0';
-                        if i2c_busy = '0' then
-                            led <= i2c_data_out;
-                            busy_count := 3;
-                        end if;
+                        -- select register DC (DAC control)
+                        i2c_data_in <= x"21";
                     when 3 =>
-                        -- finished!
+                        -- enable dac bypass and h/vsync outputs
+                        i2c_data_in <= x"09";
+
+                    when 4 =>
+                        -- select register TPCP (PLL charge pump control)
+                        i2c_data_in <= x"33";
+                    when 5 =>
+                        -- enable <= 65 MHz mode (datasheet table 10)
+                        i2c_data_in <= x"08";
+
+                    when 6 =>
+                        -- select register TPD (PLL divider)
+                        i2c_data_in <= x"34";
+                    when 7 =>
+                        -- enable <= 65 MHz mode (datasheet table 10)
+                        i2c_data_in <= x"16";
+
+                    when 8 =>
+                        -- select register TPF (PLL filter)
+                        i2c_data_in <= x"36";
+                    when 9 =>
+                        -- enable <= 65 MHz mode (datasheet table 10)
+                        i2c_data_in <= x"60";
+
+                    when 10 =>
+                        -- no more commands
+                        i2c_execute <= '0';
                         finished <= '1';
-                        null;
                 end case;
             else
                 delay := delay + 1;