4 -- File: CONFIG_RD_0.VHD
 
   7 use IEEE.std_logic_1164.all;
 
  12         ADDR_REG        :in             std_logic_vector (31 downto 0);
 
  13         CF_RD_COM       :in             std_logic;
 
  14         READ_SEL        :out    std_logic_vector ( 2 downto 0)
 
  16 end entity CONFIG_RD_0;
 
  18 architecture CONFIG_RD_0_DESIGN of CONFIG_RD_0 is
 
  25 --                             PCI Configuration Space Header
 
  29 --Address               |31               24|23           16|15            8|7             0|      
 
  30 -----------------------------------------------------------------
 
  31 --00                    |Device ID                              |Vendor ID                              |                                       
 
  32 --04                    |Status                                 |Command                                |
 
  33 --08                    |Class Code                                                     |Revision ID|
 
  34 --0C                    |BIST           |Header Type|Latency T. |Cache L.S.     |
 
  35 --10-24                 |Base Address Register                                                  |
 
  36 --28                    |Cardbus CIS Pointer                                                    |
 
  37 --2C                    |Subsystem ID                   |Subsystem Vendor ID    |
 
  38 --30                    |Expansion ROM Base Address                                             |
 
  41 --3C                    |Max_Lat        |Min_Gnt        |Int_Pin        |Int_Line       |
 
  43 -----------------------------------------------------------------
 
  47 --C/BE[3..0] Command Type
 
  48 --------------------------------------
 
  49 --      0000            Interrupt Acknowledge
 
  60 --      1010            Configuration Read
 
  61 --      1011            Configuration Write
 
  62 --      1100            Memory Read Multiple 
 
  63 --      1101            Dual Address Cycle
 
  64 --      1110            Memory Read Line
 
  65 --      1111            Memory Write and Invalidate
 
  69 --C/BE[3..0] gueltige Datenbits 
 
  70 -------------------------------
 
  76         constant        CMD_INT_ACK                     :std_logic_vector(3 downto 0) := "0000";
 
  77         constant        CMD_SP_CYC                      :std_logic_vector(3 downto 0) := "0001";
 
  78         constant        CMD_IO_READ                     :std_logic_vector(3 downto 0) := "0010";
 
  79         constant        CMD_IO_WRITE            :std_logic_vector(3 downto 0) := "0011";
 
  80         constant        CMD_RES_4                               :std_logic_vector(3 downto 0) := "0100";
 
  81         constant        CMD_RES_5                               :std_logic_vector(3 downto 0) := "0101";
 
  82         constant        CMD_MEM_READ            :std_logic_vector(3 downto 0) := "0110";
 
  83         constant        CMD_MEM_WRITE           :std_logic_vector(3 downto 0) := "0111";
 
  84         constant        CMD_RES_8                               :std_logic_vector(3 downto 0) := "1000";
 
  85         constant        CMD_RES_9                               :std_logic_vector(3 downto 0) := "1001";
 
  86         constant        CMD_CONF_READ           :std_logic_vector(3 downto 0) := "1010";
 
  87         constant        CMD_CONF_WRITE  :std_logic_vector(3 downto 0) := "1011";
 
  88         constant        CMD_MEM_READ_M  :std_logic_vector(3 downto 0) := "1100";
 
  89         constant        CMD_DU_ADR_CYC  :std_logic_vector(3 downto 0) := "1101";
 
  90         constant        CMD_MEN_READ_L  :std_logic_vector(3 downto 0) := "1110";
 
  91         constant        CMD_MEM_WRITE_I :std_logic_vector(3 downto 0) := "1111";
 
  93         signal          MUX                                                     :std_logic_vector(31 downto 0); 
 
  94         signal          CONFIG_ADDR                     :std_logic_vector( 7 downto 0); 
 
  98         CONFIG_ADDR(7 downto 0) <= ADDR_REG(7 downto 0);
 
 100 --*******************************************************************
 
 101 --*********************** PCI Read Address **************************
 
 102 --*******************************************************************
 
 104         process (CF_RD_COM, CONFIG_ADDR) 
 
 107                 if      CF_RD_COM = '1' then
 
 109                         if              CONFIG_ADDR = X"00"     then    READ_SEL <= "000";
 
 110                         elsif   CONFIG_ADDR = X"04"     then    READ_SEL <= "001";
 
 111                         elsif   CONFIG_ADDR = X"08"     then    READ_SEL <= "010";
 
 112                         elsif   CONFIG_ADDR = X"10"     then    READ_SEL <= "011";
 
 113                         elsif   CONFIG_ADDR = X"3C"     then    READ_SEL <= "100";
 
 114                         elsif   CONFIG_ADDR = X"40"     then    READ_SEL <= "101";
 
 115                         else                                                            READ_SEL <= "111";
 
 117                 else                                                                    READ_SEL <= "111";
 
 121 end architecture CONFIG_RD_0_DESIGN;