Work in progress. Added PS/2 keyboard interface, hardware debugger. Interrupt test output to 6522 (remove later). Fixed error in pin assignments that blocked access to Flash chip select. Added reading sideways ROMs from external Flash (all but BASIC masked off for now).

1 files changed, 14 insertions, 12 deletions

diff --git a/m6522.vhd b/m6522.vhd
index f0b974a..a0dd241 100644
--- a/m6522.vhd
+++ b/m6522.vhd
@@ -90,7 +90,8 @@ entity M6522 is
     I_P2_H            : in    std_logic; -- high for phase 2 clock  ____----__

     RESET_L           : in    std_logic;

     ENA_4             : in    std_logic; -- clk enable

-    CLK               : in    std_logic

+    CLK               : in    std_logic;

+    testout : out std_logic_vector(7 downto 0)

     );

 end;

 

@@ -191,6 +192,8 @@ architecture RTL of M6522 is
 

   signal final_irq         : std_logic;

 begin

+	testout <= r_ifr and "1" & r_ier;

+

   p_phase : process

   begin

     -- internal clock phase

@@ -597,17 +600,14 @@ begin
   --

   -- Timer 1

   --

-  p_timer1_done : process

+  p_timer1_done : process(t1c,phase,r_acr)

     variable done : boolean;

   begin

-    wait until rising_edge(CLK);

-    if (ENA_4 = '1') then

       done := (t1c = x"0000");

       t1c_done <= done and (phase = "11");

       if (phase = "11") then

         t1_reload_counter <= done and (r_acr(6) = '1');

       end if;

-    end if;

   end process;

 

   p_timer1 : process

@@ -626,12 +626,15 @@ begin
       elsif t1c_done then

         t1c_active <= false;

       end if;

+      if RESET_L = '0' then

+        t1c_active <= false;

+      end if;

 

       t1_toggle <= '0';

       if t1c_active and t1c_done then

         t1_toggle <= '1';

         t1_irq <= '1';

-      elsif t1_w_reset_int or t1_r_reset_int or (clear_irq(6) = '1') then

+      elsif RESET_L = '0' or t1_w_reset_int or t1_r_reset_int or (clear_irq(6) = '1') then

         t1_irq <= '0';

       end if;

     end if;

@@ -650,17 +653,14 @@ begin
     end if;

   end process;

 

-  p_timer2_done : process

+  p_timer2_done : process(t2c,phase)

     variable done : boolean;

   begin

-    wait until rising_edge(CLK);

-    if (ENA_4 = '1') then

       done := (t2c = x"0000");

       t2c_done <= done and (phase = "11");

       if (phase = "11") then

         t2_reload_counter <= done;

       end if;

-    end if;

   end process;

 

   p_timer2 : process

@@ -693,11 +693,13 @@ begin
       elsif t2c_done then

         t2c_active <= false;

       end if;

-

+      if RESET_L = '0' then

+		t2c_active <= false;

+	  end if;

 

       if t2c_active and t2c_done then

         t2_irq <= '1';

-      elsif t2_w_reset_int or t2_r_reset_int or (clear_irq(5) = '1') then

+      elsif RESET_L = '0' or t2_w_reset_int or t2_r_reset_int or (clear_irq(5) = '1') then

         t2_irq <= '0';

       end if;

     end if;