all files to lowercase,

[raggedstone] / dhwk / source / par_ser_con.vhd

diff --git a/dhwk/source/par_ser_con.vhd b/dhwk/source/par_ser_con.vhd
new file mode 100644 (file)
index 0000000..1c366e2
--- /dev/null
+++ b/dhwk/source/par_ser_con.vhd
@@ -0,0 +1,123 @@
+-- $Id: par_ser_con.vhd,v 1.1 2007-03-11 08:55:29 sithglan Exp $
+
+library ieee;
+use ieee.std_logic_1164.all;
+use ieee.std_logic_unsigned.all;
+
+entity PAR_SER_CON     is
+        port
+        (
+                PCI_CLOCK              :in     std_logic; 
+                RESET                          :in     std_logic; 
+                PSC_ENABLE                     :in     std_logic; -- Parallel Serial Converter Enable
+                SYNC_S_FIFO_EFn                        :in     std_logic; -- Empty Flag (low active)
+                SPC_RDY_IN                     :in     std_logic; -- Ready to receive data
+                PAR_IN                         :in     std_logic_vector(7 downto 0);
+                SER_OUT                                :out    std_logic; -- Serial Output
+                S_FIFO_READn                   :out    std_logic  -- FIFO Read (low active)
+        );                     
+end entity     PAR_SER_CON ;
+
+architecture PAR_SER_CON_DESIGN        of PAR_SER_CON is
+
+        constant STATE_END        :std_logic_vector(3 downto 0) := "0001";
+        constant STATE_SEND       :std_logic_vector(3 downto 0) := "0010";
+        constant STATE_SEND_BIT_0 :std_logic_vector(3 downto 0) := "0011";
+        constant STATE_SEND_BIT_1 :std_logic_vector(3 downto 0) := "0100";
+        constant STATE_SEND_BIT_2 :std_logic_vector(3 downto 0) := "0101";
+        constant STATE_SEND_BIT_3 :std_logic_vector(3 downto 0) := "0110";
+        constant STATE_SEND_BIT_4 :std_logic_vector(3 downto 0) := "0111";
+        constant STATE_SEND_BIT_5 :std_logic_vector(3 downto 0) := "1000";
+        constant STATE_SEND_BIT_6 :std_logic_vector(3 downto 0) := "1001";
+        constant STATE_SEND_BIT_7 :std_logic_vector(3 downto 0) := "1010";
+
+        signal COUNT     :std_logic_vector (3 downto 0);
+        signal STATE     :std_logic_vector (3 downto 0); 
+        signal DATUM     :std_logic_vector (7 downto 0);
+        signal SYNC                     :std_logic; -- make SPC_RDY_IN stable
+
+        attribute syn_state_machine:boolean;
+        attribute syn_state_machine of STATE: signal is false;
+        attribute syn_state_machine of COUNT: signal is false;
+begin
+
+        process(PCI_CLOCK)
+        begin
+                if (PCI_CLOCK'event and PCI_CLOCK = '1') then
+                        if ("0000" < COUNT) then
+                                COUNT <= COUNT - 1;
+                        end if;
+
+                        if (RESET = '1') then
+                                STATE <= STATE_SEND;
+                                COUNT <= "0000";
+                                SER_OUT <= '0';
+                                S_FIFO_READn <= '1';
+
+                        elsif (PSC_ENABLE = '1') then
+                                if (COUNT = "0000") then
+                                        COUNT <= "0011";
+                                        case STATE is
+                                        when STATE_SEND =>
+                                                if(SYNC = '1' and SYNC_S_FIFO_EFn = '1') then
+                                                        SER_OUT <= '1';
+                                                        S_FIFO_READn <= '0';
+                                                        STATE <= STATE_SEND_BIT_0;
+                                                end if;
+
+                                        when STATE_SEND_BIT_0 =>
+                                                DATUM     <= PAR_IN;
+                                                S_FIFO_READn <= '1';
+                                                SER_OUT <= PAR_IN(0); 
+                                                STATE <= STATE_SEND_BIT_1;
+
+                                        when STATE_SEND_BIT_1 =>
+                                                SER_OUT <= DATUM(1); 
+                                                STATE <= STATE_SEND_BIT_2;
+
+                                        when STATE_SEND_BIT_2 =>
+                                                SER_OUT <= DATUM(2); 
+                                                STATE <= STATE_SEND_BIT_3;
+
+                                        when STATE_SEND_BIT_3 =>
+                                                SER_OUT <= DATUM(3); 
+                                                STATE <= STATE_SEND_BIT_4;
+
+                                        when STATE_SEND_BIT_4 =>
+                                                SER_OUT <= DATUM(4); 
+                                                STATE <= STATE_SEND_BIT_5;
+
+                                        when STATE_SEND_BIT_5 =>
+                                                SER_OUT <= DATUM(5); 
+                                                STATE <= STATE_SEND_BIT_6;
+
+                                        when STATE_SEND_BIT_6 =>
+                                                SER_OUT <= DATUM(6); 
+                                                STATE <= STATE_SEND_BIT_7;
+
+                                        when STATE_SEND_BIT_7 =>
+                                                SER_OUT <= DATUM(7); 
+                                                STATE <= STATE_END;
+
+                                        when STATE_END =>
+                                                SER_OUT <= '0';
+                                                STATE <= STATE_SEND;
+
+                                        when others => STATE <= STATE_END;
+                                        end case;
+
+                                else
+                                        S_FIFO_READn <= '1';
+                                end if; -- COUNT
+                        end if; -- RESET ... / PSC_ENABLE ...
+                end if; -- PCI_CLOCK ...
+        end process;
+
+        process(PCI_CLOCK)
+        begin
+                if (PCI_CLOCK'event and PCI_CLOCK = '1') then
+                        SYNC <= SPC_RDY_IN;
+                end if;
+        end process;
+
+end architecture PAR_SER_CON_DESIGN;