Fixup i2c init module

dvi_test.xise

@@ -33,9 +33,6 @@
       <association xil_pn:name="BehavioralSimulation" xil_pn:seqID="65"/>
       <association xil_pn:name="Implementation" xil_pn:seqID="0"/>
     </file>
-    <file xil_pn:name="main.ucf" xil_pn:type="FILE_UCF">
-      <association xil_pn:name="Implementation" xil_pn:seqID="0"/>
-    </file>
     <file xil_pn:name="ipcore_dir/clock_source.xaw" xil_pn:type="FILE_XAW">
       <association xil_pn:name="BehavioralSimulation" xil_pn:seqID="106"/>
       <association xil_pn:name="Implementation" xil_pn:seqID="0"/>
@@ -377,8 +374,7 @@
   </properties>
 
   <bindings>
-    <binding xil_pn:location="/main" xil_pn:name="main.ucf"/>
+    <binding xil_pn:location="/init_ch7301c" xil_pn:name="init_ch7301c.ucf"/>
-    <binding xil_pn:location="/main" xil_pn:name="init_ch7301c.ucf"/>
   </bindings>
 
   <libraries/>

init_ch7301c.ucf

@@ -1,6 +1,19 @@
+NET "clk" LOC = AG18;
+NET "clk" PERIOD = 27 MHz HIGH 50%;
+NET "reset" LOC = AJ6; # center switch
 
 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;
@@ -11,5 +24,8 @@ NET "led(5)" LOC = AD25;
 NET "led(6)" LOC = AD24;
 NET "led(7)" LOC = AE24;
 
-NET "clk" LOC = AG18;
+NET "led_n" LOC = AF13;
-NET "clk" PERIOD = 27 MHz HIGH 50%;
+NET "led_e" LOC = AG23;
+NET "led_s" LOC = AG12;
+NET "led_w" LOC = AF23;
+NET "led_c" LOC = E8;

init_ch7301c.vhd

@@ -10,15 +10,28 @@ use unisim.VComponents.all;
 entity init_ch7301c is
     port (
         clk: in std_logic;
+        reset: in std_logic;
 
         i2c_scl: inout std_logic;
         i2c_sda: inout std_logic;
+        dvi_reset: out std_logic;
 
-        led: out std_logic_vector(7 downto 0)
+        dip: in std_logic_vector(7 downto 0);
+
+        led: out std_logic_vector(7 downto 0);
+
+        led_n: out std_logic;
+        led_e: out std_logic;
+        led_s: out std_logic;
+        led_w: out std_logic;
+        led_c: out std_logic
     );
 end init_ch7301c;
 
 architecture Behavioral of init_ch7301c is
+    constant i2c_ch7301c: std_logic_vector(6 downto 0) := "1110110"; -- 0x76
+
+    signal i2c_reset: std_logic := '1';
     signal i2c_execute: std_logic := '0';
     signal i2c_busy: std_logic;
     signal i2c_busy_old: std_logic;
@@ -26,6 +39,10 @@ architecture Behavioral of init_ch7301c is
     signal i2c_write: std_logic;
     signal i2c_data_in: std_logic_vector(7 downto 0);
     signal i2c_data_out: std_logic_vector(7 downto 0);
+    signal i2c_error: std_logic;
+
+    type states is (start, init, finished, error);
+    signal state: states := start;
 begin
 
     i2c_master: entity work.i2c_master generic map (
@@ -33,47 +50,90 @@ begin
         bus_clk => 100_000
     ) port map (
         clk => clk,
-        reset_n => '1',
+        reset_n => i2c_reset,
         ena => i2c_execute,
         addr => i2c_address,
         rw => not i2c_write,
         data_wr => i2c_data_in,
         busy => i2c_busy,
         data_rd => i2c_data_out,
-        ack_error => open,
+        ack_error => i2c_error,
-        sda => i2c_scl,
+        scl => i2c_scl,
-        scl => i2c_sda
+        sda => i2c_sda
     );
 
-    main: process(clk)
+    led_n <= '1' when state = start else '0';
-        variable busy_count: integer range 0 to 3 := 0;
+    led_e <= '1' when state = init else '0';
-    begin
+    led_s <= '1' when state = finished else '0';
-        if rising_edge(clk) then
+    led_w <= '1' when state = error else '0';
-            i2c_busy_old <= i2c_busy; -- remember old value
+    led_c <= reset;
-            if i2c_busy_old = '0' and i2c_busy = '1' then
-                -- count rising edges on i2c_busy:
-                -- command was ascepted, read for new one
-                busy_count := busy_count + 1;
-            end if;
 
-            case busy_count is
+    main: process(clk, reset)
-                when 0 =>
+        variable delay_init: integer range 0 to 10_000 := 0;
-                    -- no command eccepted yet, insert first one
+        variable busy_count: integer range 0 to 2 := 0;
-                    i2c_execute <= '1';
+    begin
-                    i2c_write <= '1';
+        if reset = '1' then
-                    i2c_address <= "0111011"; -- 0x76
+            busy_count := 0;
-                    i2c_data_in <= "01001001"; -- read power status of the chip (0x49)
+            delay_init := 0;
-                when 1 =>
+            state <= start;
-                    -- submit read command
+
-                    i2c_write <= '0';
+            -- reset components
-                when 2 =>
+            dvi_reset <= '0';
-                    -- read submitted, wait for results, no more commands
+            i2c_reset <= '0';
-                    i2c_execute <= '0';
+        elsif rising_edge(clk) then
-                    if i2c_busy = '0' then
+            case state is
-                        led <= not i2c_data_out;
+                when start =>
+                    delay_init := delay_init + 1;
+
+                    if delay_init = 5_000 then
+                        -- start components
+                        dvi_reset <= '1';
+                        i2c_reset <= '1';
+                    elsif delay_init = 10_000 then
+                        delay_init := 0;
+                        -- start i2c init
+                        state <= init;
+                        busy_count := 0;
                     end if;
-                when 3 =>
+
-                    -- finnished, stay here
+                when init =>
+                    i2c_busy_old <= i2c_busy; -- remember old value
+                    if i2c_busy_old = '0' and i2c_busy = '1' then
+                        -- count rising edges on i2c_busy:
+                        -- command was accepted, ready for new one
+                        busy_count := busy_count + 1;
+                    end if;
+
+                    if i2c_error = '1' then
+                        -- abort on error
+                        i2c_execute <= '0';
+                        state <= error;
+                    end if;
+
+                    case busy_count is
+                        when 0 =>
+                            -- no command accepted yet, insert first one
+                            i2c_execute <= '1';
+                            i2c_write <= '1';
+                            i2c_address <= i2c_ch7301c;
+                            i2c_data_in <= dip;
+                        when 1 =>
+                            -- submit read command
+                            i2c_write <= '0';
+                        when 2 =>
+                            -- read submitted, wait for results, no more commands
+                            i2c_execute <= '0';
+                            if i2c_busy = '0' then
+                                led <= i2c_data_out;
+                                busy_count := 0;
+                                state <= finished;
+                            end if;
+                    end case;
+
+                when finished =>
+                    null;
+
+                when error =>
                     null;
             end case;
         end if;