can_acf.v

一个用硬件描述语言编写CAN总线控制器的IP

                        (rtr1   == acceptance_code_1[4] | acceptance_mask_1[4] ) &
                        (id[0]  == acceptance_code_1[5] | acceptance_mask_1[5] ) &
                        (id[1]  == acceptance_code_1[6] | acceptance_mask_1[6] ) &
                        (id[2]  == acceptance_code_1[7] | acceptance_mask_1[7] ) &

                        (data0[0]  == acceptance_code_2[0] | acceptance_mask_2[0] | no_byte0) &
                        (data0[1]  == acceptance_code_2[1] | acceptance_mask_2[1] | no_byte0) &
                        (data0[2]  == acceptance_code_2[2] | acceptance_mask_2[2] | no_byte0) &
                        (data0[3]  == acceptance_code_2[3] | acceptance_mask_2[3] | no_byte0) &
                        (data0[4]  == acceptance_code_2[4] | acceptance_mask_2[4] | no_byte0) &
                        (data0[5]  == acceptance_code_2[5] | acceptance_mask_2[5] | no_byte0) &
                        (data0[6]  == acceptance_code_2[6] | acceptance_mask_2[6] | no_byte0) &
                        (data0[7]  == acceptance_code_2[7] | acceptance_mask_2[7] | no_byte0) &

                        (data1[0]  == acceptance_code_3[0] | acceptance_mask_3[0] | no_byte1) &
                        (data1[1]  == acceptance_code_3[1] | acceptance_mask_3[1] | no_byte1) &
                        (data1[2]  == acceptance_code_3[2] | acceptance_mask_3[2] | no_byte1) &
                        (data1[3]  == acceptance_code_3[3] | acceptance_mask_3[3] | no_byte1) &
                        (data1[4]  == acceptance_code_3[4] | acceptance_mask_3[4] | no_byte1) &
                        (data1[5]  == acceptance_code_3[5] | acceptance_mask_3[5] | no_byte1) &
                        (data1[6]  == acceptance_code_3[6] | acceptance_mask_3[6] | no_byte1) &
                        (data1[7]  == acceptance_code_3[7] | acceptance_mask_3[7] | no_byte1)
                      );



// Working in extended mode. ID match for extended format (29-bit ID). Using single filter.
assign match_sf_ext = ( (id[21]  == acceptance_code_0[0] | acceptance_mask_0[0] ) &
                        (id[22]  == acceptance_code_0[1] | acceptance_mask_0[1] ) &
                        (id[23]  == acceptance_code_0[2] | acceptance_mask_0[2] ) &
                        (id[24]  == acceptance_code_0[3] | acceptance_mask_0[3] ) &
                        (id[25]  == acceptance_code_0[4] | acceptance_mask_0[4] ) &
                        (id[26]  == acceptance_code_0[5] | acceptance_mask_0[5] ) &
                        (id[27]  == acceptance_code_0[6] | acceptance_mask_0[6] ) &
                        (id[28]  == acceptance_code_0[7] | acceptance_mask_0[7] ) &

                        (id[13]  == acceptance_code_1[0] | acceptance_mask_1[0] ) &
                        (id[14]  == acceptance_code_1[1] | acceptance_mask_1[1] ) &
                        (id[15]  == acceptance_code_1[2] | acceptance_mask_1[2] ) &
                        (id[16]  == acceptance_code_1[3] | acceptance_mask_1[3] ) &
                        (id[17]  == acceptance_code_1[4] | acceptance_mask_1[4] ) &
                        (id[18]  == acceptance_code_1[5] | acceptance_mask_1[5] ) &
                        (id[19]  == acceptance_code_1[6] | acceptance_mask_1[6] ) &
                        (id[20]  == acceptance_code_1[7] | acceptance_mask_1[7] ) &

                        (id[5]  == acceptance_code_2[0] | acceptance_mask_2[0] ) &
                        (id[6]  == acceptance_code_2[1] | acceptance_mask_2[1] ) &
                        (id[7]  == acceptance_code_2[2] | acceptance_mask_2[2] ) &
                        (id[8]  == acceptance_code_2[3] | acceptance_mask_2[3] ) &
                        (id[9]  == acceptance_code_2[4] | acceptance_mask_2[4] ) &
                        (id[10] == acceptance_code_2[5] | acceptance_mask_2[5] ) &
                        (id[11] == acceptance_code_2[6] | acceptance_mask_2[6] ) &
                        (id[12] == acceptance_code_2[7] | acceptance_mask_2[7] ) &

                        (rtr2   == acceptance_code_3[2] | acceptance_mask_3[2] ) &
                        (id[0]  == acceptance_code_3[3] | acceptance_mask_3[3] ) &
                        (id[1]  == acceptance_code_3[4] | acceptance_mask_3[4] ) &
                        (id[2]  == acceptance_code_3[5] | acceptance_mask_3[5] ) &
                        (id[3]  == acceptance_code_3[6] | acceptance_mask_3[6] ) &
                        (id[4]  == acceptance_code_3[7] | acceptance_mask_3[7] )

                      );


// Working in extended mode. ID match for standard format (11-bit ID). Using double filter.
assign match_df_std = (((id[3]  == acceptance_code_0[0] | acceptance_mask_0[0] ) &
                        (id[4]  == acceptance_code_0[1] | acceptance_mask_0[1] ) &
                        (id[5]  == acceptance_code_0[2] | acceptance_mask_0[2] ) &
                        (id[6]  == acceptance_code_0[3] | acceptance_mask_0[3] ) &
                        (id[7]  == acceptance_code_0[4] | acceptance_mask_0[4] ) &
                        (id[8]  == acceptance_code_0[5] | acceptance_mask_0[5] ) &
                        (id[9]  == acceptance_code_0[6] | acceptance_mask_0[6] ) &
                        (id[10] == acceptance_code_0[7] | acceptance_mask_0[7] ) &

                        (rtr1   == acceptance_code_1[4] | acceptance_mask_1[4] ) &
                        (id[0]  == acceptance_code_1[5] | acceptance_mask_1[5] ) &
                        (id[1]  == acceptance_code_1[6] | acceptance_mask_1[6] ) &
                        (id[2]  == acceptance_code_1[7] | acceptance_mask_1[7] ) &

                        (data0[0] == acceptance_code_3[0] | acceptance_mask_3[0] | no_byte0) &
                        (data0[1] == acceptance_code_3[1] | acceptance_mask_3[1] | no_byte0) &
                        (data0[2] == acceptance_code_3[2] | acceptance_mask_3[2] | no_byte0) &
                        (data0[3] == acceptance_code_3[3] | acceptance_mask_3[3] | no_byte0) &
                        (data0[4] == acceptance_code_1[4] | acceptance_mask_1[4] | no_byte0) &
                        (data0[5] == acceptance_code_1[5] | acceptance_mask_1[5] | no_byte0) &
                        (data0[6] == acceptance_code_1[6] | acceptance_mask_1[6] | no_byte0) &
                        (data0[7] == acceptance_code_1[7] | acceptance_mask_1[7] | no_byte0) )
                        
                       |

                       ((id[3]  == acceptance_code_2[0] | acceptance_mask_2[0] ) &
                        (id[4]  == acceptance_code_2[1] | acceptance_mask_2[1] ) &
                        (id[5]  == acceptance_code_2[2] | acceptance_mask_2[2] ) &
                        (id[6]  == acceptance_code_2[3] | acceptance_mask_2[3] ) &
                        (id[7]  == acceptance_code_2[4] | acceptance_mask_2[4] ) &
                        (id[8]  == acceptance_code_2[5] | acceptance_mask_2[5] ) &
                        (id[9]  == acceptance_code_2[6] | acceptance_mask_2[6] ) &
                        (id[10] == acceptance_code_2[7] | acceptance_mask_2[7] ) &

                        (rtr1   == acceptance_code_3[4] | acceptance_mask_3[4] ) &
                        (id[0]  == acceptance_code_3[5] | acceptance_mask_3[5] ) &
                        (id[1]  == acceptance_code_3[6] | acceptance_mask_3[6] ) &
                        (id[2]  == acceptance_code_3[7] | acceptance_mask_3[7] ) )

                      );


// Working in extended mode. ID match for extended format (29-bit ID). Using double filter.
assign match_df_ext = (((id[21]  == acceptance_code_0[0] | acceptance_mask_0[0] ) &
                        (id[22]  == acceptance_code_0[1] | acceptance_mask_0[1] ) &
                        (id[23]  == acceptance_code_0[2] | acceptance_mask_0[2] ) &
                        (id[24]  == acceptance_code_0[3] | acceptance_mask_0[3] ) &
                        (id[25]  == acceptance_code_0[4] | acceptance_mask_0[4] ) &
                        (id[26]  == acceptance_code_0[5] | acceptance_mask_0[5] ) &
                        (id[27]  == acceptance_code_0[6] | acceptance_mask_0[6] ) &
                        (id[28]  == acceptance_code_0[7] | acceptance_mask_0[7] ) &

                        (id[13]  == acceptance_code_1[0] | acceptance_mask_1[0] ) &
                        (id[14]  == acceptance_code_1[1] | acceptance_mask_1[1] ) &
                        (id[15]  == acceptance_code_1[2] | acceptance_mask_1[2] ) &
                        (id[16]  == acceptance_code_1[3] | acceptance_mask_1[3] ) &
                        (id[17]  == acceptance_code_1[4] | acceptance_mask_1[4] ) &
                        (id[18]  == acceptance_code_1[5] | acceptance_mask_1[5] ) &
                        (id[19]  == acceptance_code_1[6] | acceptance_mask_1[6] ) &
                        (id[20]  == acceptance_code_1[7] | acceptance_mask_1[7] ) )
                        
                       |
                        
                       ((id[21]  == acceptance_code_2[0] | acceptance_mask_2[0] ) &
                        (id[22]  == acceptance_code_2[1] | acceptance_mask_2[1] ) &
                        (id[23]  == acceptance_code_2[2] | acceptance_mask_2[2] ) &
                        (id[24]  == acceptance_code_2[3] | acceptance_mask_2[3] ) &
                        (id[25]  == acceptance_code_2[4] | acceptance_mask_2[4] ) &
                        (id[26]  == acceptance_code_2[5] | acceptance_mask_2[5] ) &
                        (id[27]  == acceptance_code_2[6] | acceptance_mask_2[6] ) &
                        (id[28]  == acceptance_code_2[7] | acceptance_mask_2[7] ) &

                        (id[13]  == acceptance_code_3[0] | acceptance_mask_3[0] ) &
                        (id[14]  == acceptance_code_3[1] | acceptance_mask_3[1] ) &
                        (id[15]  == acceptance_code_3[2] | acceptance_mask_3[2] ) &
                        (id[16]  == acceptance_code_3[3] | acceptance_mask_3[3] ) &
                        (id[17]  == acceptance_code_3[4] | acceptance_mask_3[4] ) &
                        (id[18]  == acceptance_code_3[5] | acceptance_mask_3[5] ) &
                        (id[19]  == acceptance_code_3[6] | acceptance_mask_3[6] ) &
                        (id[20]  == acceptance_code_3[7] | acceptance_mask_3[7] ) )
                      );



// ID ok signal generation
always @ (posedge clk or posedge rst)
begin
  if (rst)
    id_ok <= 1'b0;
  else if (go_rx_crc_lim)                   // sample_point is already included in go_rx_crc_lim
    begin
      if (extended_mode)
        begin
          if (~acceptance_filter_mode)      // dual filter
            begin
              if (ide)                      // extended frame message
                id_ok <=#Tp match_df_ext;
              else                          // standard frame message
                id_ok <=#Tp match_df_std;
            end           
          else                              // single filter
            begin
              if (ide)                      // extended frame message
                id_ok <=#Tp match_sf_ext;
              else                          // standard frame message
                id_ok <=#Tp match_sf_std;
            end
        end
      else      
        id_ok <=#Tp match;
    end
  else if (reset_mode | go_rx_inter | go_error_frame)        // sample_point is already included in go_rx_inter
    id_ok <=#Tp 1'b0;
end









endmodule