src/parser.vhd

   1 library ieee;
   2 use ieee.std_logic_1164.all;
   3 use ieee.numeric_std.all;
   4 use work.gen_pkg.all;
   5
   6 entity parser is
   7         port
   8         (
   9                 sys_clk : in std_logic;
  10                 sys_res_n : in std_logic;
  11                 -- History
  12                 p_rw : out std_logic;
  13                 p_spalte : out hspalte;
  14                 p_rget : out std_logic;
  15                 p_rdone : in std_logic;
  16                 p_read : in hbyte;
  17                 p_wtake : out std_logic;
  18                 p_wdone : in std_logic;
  19                 p_write : out hbyte;
  20                 p_finished : out std_logic;
  21                 -- Scanner
  22                 do_it : in std_logic;
  23                 finished : out std_logic
  24         );
  25 end entity parser;
  26
  27 architecture beh of parser is
  28         type PARSER_STATE is (SIDLE, SREAD_NEWNUMBER, SREAD_SPACE1_2,
  29         SREAD_SPACE1_3, SREAD_SPACE2, SREAD_SPACE3, SREAD_OP1, SREAD_OP2,
  30         SREAD_SIGN1, SREAD_NEXTBYTE, SREAD_CALCNUMBER1, SREAD_CALCNUMBER2, SCALC_1,
  31         SCALC_14, SCALC_15, SCALC_2, SWRITE_CHAR0, SWRITE_CHAR1, SWRITE_CHAR2,
  32         SWRITE_SIGN1, SWRITE_SIGN2, SDONE, SERROR1, SERROR2);
  33         signal state_int, state_next : PARSER_STATE;
  34         signal z_int, z_next, strich_int, strich_next, wtmp_int, wtmp_next : csigned;
  35         signal punkt_int, punkt_next : csigned;
  36         signal rbyte_int, rbyte_next : hbyte;
  37         signal p_write_int, p_write_next : hbyte;
  38         signal p_rget_int, p_rget_next : std_logic;
  39         signal p_wtake_int, p_wtake_next : std_logic;
  40         signal p_finished_int, p_finished_next : std_logic;
  41         signal aktop_int, aktop_next : alu_ops;
  42         signal opp_int, opp_next : alu_ops;
  43         signal opcode_int, opcode_next : alu_ops;
  44         signal op1_int, op1_next : csigned;
  45         signal op2_int, op2_next : csigned;
  46         signal do_calc_int, do_calc_next : std_logic;
  47         signal goto_calcn1, goto_op1, goto_space3, goto_sign : std_logic;
  48         signal z_sign_next, z_sign_int : std_logic;
  49         signal firstz_next, firstz_int : boolean;
  50         signal err_next, err_int : hstr_int;
  51         signal errc_next, errc_int : hstr_int;
  52         signal errc_tmp_next, errc_tmp_int : hstr_int;
  53         -- ALU
  54         signal opcode : alu_ops;
  55         signal op1 : csigned;
  56         signal op2 : csigned;
  57         signal op3 : csigned;
  58         signal opM : csigned;
  59         signal do_calc : std_logic;
  60         signal calc_done : std_logic;
  61         signal calc_error : std_logic;
  62 begin
  63         instalu : entity work.alu(beh)
  64         port map
  65         (
  66                 sys_clk => sys_clk,
  67                 sys_res_n => sys_res_n,
  68                 do_calc => do_calc,
  69                 calc_done => calc_done,
  70                 calc_error => calc_error,
  71                 op1 => op1,
  72                 op2 => op2,
  73                 op3 => op3,
  74                 opM => opM,
  75                 opcode => opcode
  76         );
  77
  78         p_write <= p_write_int;
  79         p_rget <= p_rget_int;
  80         p_wtake <= p_wtake_int;
  81         p_finished <= p_finished_int;
  82
  83         opcode <= opcode_int;
  84         op1 <= op1_int;
  85         op2 <= op2_int;
  86         do_calc <= do_calc_int;
  87
  88         process(sys_clk, sys_res_n)
  89         begin
  90                 if sys_res_n = '0' then
  91                         state_int <= SIDLE;
  92                         z_int <= (others => '0');
  93                         z_sign_int <= '0';
  94                         strich_int <= (others => '0');
  95                         punkt_int <= (others => '0');
  96                         wtmp_int <= (others => '0');
  97                         rbyte_int <= (others => '0');
  98                         aktop_int <= ALU_NOP;
  99                         opp_int <= ALU_NOP;
 100                         err_int <= 0;
 101                         errc_int <= 71;
 102                         errc_tmp_int <= 0;
 103                         firstz_int <= true;
 104                         -- out ports
 105                         p_rw <= '0';
 106                         p_spalte <= (others => '0');
 107                         p_rget_int <= '0';
 108                         p_write_int <= (others => '0');
 109                         p_wtake_int <= '0';
 110                         p_finished_int <= '0';
 111                         opcode_int <= ALU_NOP;
 112                         op1_int <= (others => '0');
 113                         op2_int <= (others => '0');
 114                         do_calc_int <= '0';
 115                         finished <= '0';
 116                 elsif rising_edge(sys_clk) then
 117                         -- internal
 118                         state_int <= state_next;
 119                         z_int <= z_next;
 120                         z_sign_int <= z_sign_next;
 121                         strich_int <= strich_next;
 122                         punkt_int <= punkt_next;
 123                         wtmp_int <= wtmp_next;
 124                         rbyte_int <= rbyte_next;
 125                         aktop_int <= aktop_next;
 126                         opp_int <= opp_next;
 127                         err_int <= err_next;
 128                         errc_int <= errc_next;
 129                         errc_tmp_int <= errc_tmp_next;
 130                         firstz_int <= firstz_next;
 131                         -- out ports
 132                         p_rget_int <= p_rget_next;
 133                         p_write_int <= p_write_next;
 134                         p_wtake_int <= p_wtake_next;
 135                         p_finished_int <= p_finished_next;
 136                         opcode_int <= opcode_next;
 137                         op1_int <= op1_next;
 138                         op2_int <= op2_next;
 139                         do_calc_int <= do_calc_next;
 140                 end if;
 141         end process;
 142
 143         -- next state
 144         process(state_int, do_it, p_rdone, p_wdone, p_read, aktop_int, strich_int,
 145                 punkt_int, calc_done, wtmp_int, opp_int, goto_calcn1, goto_op1,
 146                 goto_space3, goto_sign, z_sign_int, err_int, errc_int, calc_error,
 147                 op2_int)
 148         begin
 149                 state_next <= state_int;
 150
 151                 case state_int is
 152                         when SIDLE =>
 153                                 if do_it = '1' then
 154                                         state_next <= SREAD_NEWNUMBER;
 155                                 end if;
 156                         when SREAD_NEWNUMBER =>
 157                                 state_next <= SREAD_SPACE1_2;
 158                         when SREAD_SPACE1_2 =>
 159                                 if p_rdone = '1' then
 160                                         state_next <= SREAD_SPACE2;
 161                                 end if;
 162                         when SREAD_SPACE1_3 =>
 163                                 if p_rdone = '1' then
 164                                         state_next <= SREAD_SPACE3;
 165                                 end if;
 166                         when SREAD_SPACE2 | SREAD_SPACE3 =>
 167                                 if goto_calcn1 = '1' then
 168                                         case state_int is
 169                                                 when SREAD_SPACE2 => state_next <= SREAD_NEXTBYTE;
 170                                                 when SREAD_SPACE3 => state_next <= SREAD_OP1;
 171                                                 when others => assert(false) report "wtf @ state2";
 172                                         end case;
 173                                 end if;
 174                                 if goto_sign = '1' then
 175                                         case state_int is
 176                                                 when SREAD_SPACE2 => state_next <= SREAD_SIGN1;
 177                                                 when others => assert(false) report "wtf @ state3";
 178                                         end case;
 179                                 end if;
 180                                 if p_rdone = '0' then
 181                                         if goto_calcn1 = '0' then
 182                                                 case state_int is
 183                                                         when SREAD_SPACE2 => state_next <= SREAD_SPACE1_2;
 184                                                         when SREAD_SPACE3 => state_next <= SREAD_SPACE1_3;
 185                                                         when others => assert(false) report "wtf @ state1";
 186                                                 end case;
 187                                         end if;
 188                                 end if;
 189                         when SREAD_SIGN1 =>
 190                                 if p_rdone = '0' then
 191                                         state_next <= SREAD_NEXTBYTE;
 192                                 end if;
 193                         when SREAD_NEXTBYTE =>
 194                                 if p_rdone = '1' then
 195                                         state_next <= SREAD_CALCNUMBER1;
 196                                 end if;
 197                         when SREAD_CALCNUMBER1 =>
 198                                 if goto_op1 = '1' then
 199                                         state_next <= SREAD_OP1;
 200                                 elsif goto_space3 = '1' then
 201                                         state_next <= SREAD_SPACE3;
 202                                 elsif calc_done = '1' then
 203                                         state_next <= SREAD_CALCNUMBER2;
 204                                 end if;
 205                         when SREAD_OP1 =>
 206                                 state_next <= SREAD_OP2;
 207                         when SREAD_OP2 =>
 208                                 if p_rdone = '0' then
 209                                         if aktop_int /= ALU_NOP then
 210                                                 state_next <= SCALC_1;
 211                                         end if;
 212                                 end if;
 213                         when SREAD_CALCNUMBER2 =>
 214                                 if p_rdone = '0' and calc_done = '0' then
 215                                         state_next <= SREAD_NEXTBYTE;
 216                                 end if;
 217                         when SCALC_1 =>
 218                                 if calc_done = '1' then
 219                                         case opp_int is
 220                                                 -- spezialfall: eine zwischenberechnung wird fuer diese
 221                                                 -- kombination benoetigt
 222                                                 when ALU_MUL | ALU_DIV =>
 223                                                         case aktop_int is
 224                                                                 when ALU_ADD | ALU_SUB | ALU_DONE => state_next <= SCALC_14;
 225                                                                 when others => state_next <= SCALC_2;
 226                                                         end case;
 227                                                 when others => state_next <= SCALC_2;
 228                                         end case;
 229                                 end if;
 230                         when SCALC_14 =>
 231                                 if calc_done = '0' then
 232                                         state_next <= SCALC_15;
 233                                 end if;
 234                         when SCALC_15 =>
 235                                 if calc_done = '1' then
 236                                         state_next <= SCALC_2;
 237                                 end if;
 238                         when SCALC_2 =>
 239                                 if calc_done = '0' then
 240                                         if aktop_int = ALU_DONE then
 241                                                 state_next <= SWRITE_CHAR2;
 242                                         else
 243                                                 state_next <= SREAD_NEWNUMBER;
 244                                         end if;
 245                                 end if;
 246                         when SWRITE_CHAR0 =>
 247                                 if calc_done = '1' then
 248                                         state_next <= SWRITE_CHAR1;
 249                                 end if;
 250                         when SWRITE_CHAR1 =>
 251                                 if p_wdone = '1' then
 252                                         if strich_int < 10 then
 253                                                 if z_sign_int = '1' then
 254                                                         state_next <= SWRITE_SIGN1;
 255                                                 else
 256                                                         state_next <= SDONE;
 257                                                 end if;
 258                                         else
 259                                                 state_next <= SWRITE_CHAR2;
 260                                         end if;
 261                                 end if;
 262                         when SERROR1 =>
 263                                 if p_wdone = '1' then
 264                                         if errc_int <= 2 then
 265                                                 state_next <= SDONE;
 266                                         else
 267                                                 state_next <= SERROR2;
 268                                         end if;
 269                                 end if;
 270                         when SERROR2 =>
 271                                 if p_wdone = '0' then
 272                                         state_next <= SERROR1;
 273                                 end if;
 274                         when SWRITE_CHAR2 =>
 275                                 if p_wdone = '0' and calc_done = '0' then
 276                                         state_next <= SWRITE_CHAR0;
 277                                 end if;
 278                         when SWRITE_SIGN1 =>
 279                                 if p_wdone = '0' then
 280                                         state_next <= SWRITE_SIGN2;
 281                                 end if;
 282                         when SWRITE_SIGN2 =>
 283                                 if p_wdone = '1' then
 284                                         state_next <= SDONE;
 285                                 end if;
 286
 287                         when SDONE =>
 288                                 if p_wdone = '0' and do_it = '0' then
 289                                         state_next <= SIDLE;
 290                                 end if;
 291                 end case;
 292
 293                 -- fehlerbehandlung
 294                 case state_int is
 295                         when SERROR1 | SERROR2 | SDONE => null;
 296                         when others =>
 297                                 if err_int > 0 then
 298                                         state_next <= SERROR1;
 299                                 end if;
 300                 end case;
 301         end process;
 302
 303         -- out
 304         process(state_int, p_read, p_write_int, z_int, rbyte_int, p_rget_int,
 305                 strich_int, aktop_int, opp_int, opcode_int, op1_int, op2_int, op3, opM,
 306                 do_calc_int, wtmp_int, punkt_int, z_sign_int, err_int, errc_int,
 307                 errc_tmp_int, firstz_int, calc_done, calc_error)
 308                 function hbyte2csigned (x : hbyte) return csigned is
 309                         variable y : csigned;
 310                 begin
 311                         case x is
 312                                 when x"30" => y := x"00000000";
 313                                 when x"31" => y := x"00000001";
 314                                 when x"32" => y := x"00000002";
 315                                 when x"33" => y := x"00000003";
 316                                 when x"34" => y := x"00000004";
 317                                 when x"35" => y := x"00000005";
 318                                 when x"36" => y := x"00000006";
 319                                 when x"37" => y := x"00000007";
 320                                 when x"38" => y := x"00000008";
 321                                 when x"39" => y := x"00000009";
 322                                 when others => assert(false) report "hbyte2csigned: shouldn't happen";
 323                         end case;
 324                         return y;
 325                 end function hbyte2csigned;
 326
 327                 function csigned2hbyte (x : csigned) return hbyte is
 328                         variable y : hbyte;
 329                 begin
 330                         case x is
 331                                 when x"00000000" => y := x"30";
 332                                 when x"00000001" => y := x"31";
 333                                 when x"00000002" => y := x"32";
 334                                 when x"00000003" => y := x"33";
 335                                 when x"00000004" => y := x"34";
 336                                 when x"00000005" => y := x"35";
 337                                 when x"00000006" => y := x"36";
 338                                 when x"00000007" => y := x"37";
 339                                 when x"00000008" => y := x"38";
 340                                 when x"00000009" => y := x"39";
 341                                 when others => assert(false) report "csigned2hbyte: shouldn't happen";
 342                         end case;
 343                         return y;
 344                 end function csigned2hbyte;
 345
 346
 347                 variable multmp : signed(((2*CBITS)-1) downto 0);
 348                 variable tmp : csigned;
 349
 350                 type errstrings is array (natural range 1 to 3) of hstring;
 351                 constant error_str : errstrings := (
 352                         1 => "                                                    Division durch Null" & nul,
 353                         2 => "                                                                 Syntax" & nul,
 354                         3 => "                                                   Over- bzw. Underflow" & nul
 355                 );
 356         begin
 357                 -- internal
 358                 z_next <= z_int;
 359                 z_sign_next <= z_sign_int;
 360                 strich_next <= strich_int;
 361                 punkt_next <= punkt_int;
 362                 wtmp_next <= wtmp_int;
 363                 rbyte_next <= rbyte_int;
 364                 aktop_next <= aktop_int;
 365                 opp_next <= opp_int;
 366                 err_next <= err_int;
 367                 errc_next <= errc_int;
 368                 errc_tmp_next <= errc_tmp_int;
 369                 firstz_next <= firstz_int;
 370                 -- signals
 371                 p_rget_next <= '0';
 372                 p_write_next <= p_write_int;
 373                 p_wtake_next <= '0';
 374                 p_finished_next <= '0';
 375                 opcode_next <= opcode_int;
 376                 op1_next <= op1_int;
 377                 op2_next <= op2_int;
 378                 do_calc_next <= '0';
 379                 goto_calcn1 <= '0';
 380                 goto_op1 <= '0';
 381                 goto_space3 <= '0';
 382                 goto_sign <= '0';
 383
 384                 case state_int is
 385                         when SIDLE =>
 386                                 strich_next <= (others => '0');
 387                                 punkt_next <= (0 => '1', others => '0');
 388                                 opp_next <= ALU_NOP;
 389                         when SREAD_NEWNUMBER =>
 390                                 z_next <= (others => '0');
 391                                 z_sign_next <= '0';
 392                                 firstz_next <= true;
 393                                 rbyte_next <= (others => '0');
 394                                 p_write_next <= (others => '0');
 395                                 aktop_next <= ALU_NOP;
 396                         when SREAD_NEXTBYTE | SREAD_SPACE1_2 | SREAD_SPACE1_3 =>
 397                                 p_rget_next <= '1';
 398                         when SREAD_SPACE2 | SREAD_SPACE3 =>
 399                                 case p_read is
 400                                         when x"20" =>
 401                                                 null;
 402                                         when x"2D" =>
 403                                                 case state_int is
 404                                                         when SREAD_SPACE2 => goto_sign <= '1';
 405                                                         when SREAD_SPACE3 => goto_calcn1 <= '1'; p_rget_next <= '1';
 406                                                         when others => assert(false) report "SREAD_SPACE2/3: shouldn't happen";
 407                                                 end case;
 408                                         when others =>
 409                                                 goto_calcn1 <= '1';
 410                                                 p_rget_next <= '1';
 411                                 end case;
 412
 413                         when SREAD_CALCNUMBER1 =>
 414                                 case p_read is
 415                                         -- '+', '-', '*', '/'
 416                                         when x"2B" | x"2D" | x"2A" | x"2F" | x"00" =>
 417                                                 if firstz_int then
 418                                                         err_next <= 2;
 419                                                 else
 420                                                         goto_op1 <= '1';
 421                                                         p_rget_next <= '1';
 422                                                 end if;
 423
 424                                         -- ' '
 425                                         when x"20" =>
 426                                                 goto_space3 <= '1';
 427                                                 p_rget_next <= '1';
 428
 429                                         when others =>
 430                                                 op1_next <= z_int;
 431                                                 opcode_next <= ALU_MUL;
 432                                                 op2_next <= to_signed(10,CBITS);
 433                                                 firstz_next <= false;
 434                                                 do_calc_next <= '1';
 435                                 end case;
 436                         when SREAD_SIGN1 =>
 437                                 z_sign_next <= '1';
 438                         when SREAD_CALCNUMBER2 =>
 439                                 z_next <= op3 + hbyte2csigned(p_read);
 440                         when SREAD_OP2 =>
 441                                 null;
 442                         when SREAD_OP1 =>
 443                                 case p_read is
 444                                         when x"2B" => aktop_next <= ALU_ADD; -- '+'
 445                                         when x"2D" => aktop_next <= ALU_SUB; -- '-'
 446                                         when x"2A" => aktop_next <= ALU_MUL; -- '*'
 447                                         when x"2F" => aktop_next <= ALU_DIV; -- '/'
 448                                         when x"00" => aktop_next <= ALU_DONE; -- '\0'
 449
 450                                         when others => err_next <= 2;
 451                                 end case;
 452
 453
 454                         when SCALC_1 =>
 455                                 if z_sign_int = '1' then
 456                                         tmp := (not z_int) + 1;
 457                                         z_next <= tmp;
 458                                         z_sign_next <= '0';
 459                                 else
 460                                         tmp := z_int;
 461                                 end if;
 462
 463                                 case opp_int is
 464                                         when ALU_NOP | ALU_ADD | ALU_SUB =>
 465                                                 case opp_int  is
 466                                                         when ALU_SUB => op1_next <= (not tmp) + 1;
 467                                                         when others => op1_next <= tmp;
 468                                                 end case;
 469                                                 case aktop_int is
 470                                                         when ALU_ADD | ALU_SUB | ALU_DONE =>
 471                                                                 opcode_next <= ALU_ADD;
 472                                                                 op2_next <= strich_int;
 473                                                         when ALU_MUL | ALU_DIV =>
 474                                                                 opcode_next <= ALU_MUL;
 475                                                                 op2_next <= punkt_int;
 476                                                         when others => assert(false) report "SCALC_1/1: shouldn't happen!";
 477                                                 end case;
 478
 479                                         when ALU_MUL | ALU_DIV =>
 480                                                 case aktop_int is
 481                                                         when ALU_ADD | ALU_SUB | ALU_DONE | ALU_MUL | ALU_DIV =>
 482                                                                 op1_next <= punkt_int;
 483                                                                 opcode_next <= opp_int;
 484                                                                 op2_next <= tmp;
 485                                                         when others => assert(false) report "SCALC_1/2: shouldn't happen!";
 486                                                 end case;
 487                                         when others => assert(false) report "SCALC_1/3: shouldn't happen!";
 488                                 end case;
 489                                 do_calc_next <= '1';
 490
 491                         when SCALC_14 =>
 492                                 -- ueberpruefung kann man sich sparen, da diese ohnehin in
 493                                 -- nextstate gemacht wird.
 494                                 op1_next <= op3;
 495                                 do_calc_next <= '0';
 496
 497                         when SCALC_15 =>
 498                                 -- ueberpruefung kann man sich sparen, da diese ohnehin in
 499                                 -- nextstate gemacht wird.
 500                                 opcode_next <= ALU_ADD;
 501                                 op2_next <= strich_int;
 502                                 punkt_next <= (0 => '1', others => '0');
 503                                 do_calc_next <= '1';
 504
 505                         when SCALC_2 =>
 506                                 case opp_int is
 507                                         when ALU_NOP | ALU_ADD | ALU_SUB | ALU_MUL | ALU_DIV =>
 508                                                 case aktop_int is
 509                                                         when ALU_ADD | ALU_SUB | ALU_DONE =>
 510                                                                 if aktop_int = ALU_DONE and op3 < 0 then
 511                                                                         strich_next <= (not op3) + 1;
 512                                                                         wtmp_next <= (not op3) + 1;
 513                                                                         z_sign_next <= '1';
 514                                                                 else
 515                                                                         strich_next <= op3;
 516                                                                         wtmp_next <= op3;
 517                                                                 end if;
 518                                                         when ALU_MUL | ALU_DIV =>
 519                                                                 punkt_next <= op3;
 520                                                         when others => assert (false) report "SCALC_2/1: shouldn't happen!";
 521                                                 end case;
 522                                         when others => assert (false) report "SCALC_2/2: shouldn't happen!";
 523                                 end case;
 524                                 -- aktuelle rechenoperation fuer naechste 'runde' uebernehmen
 525                                 opp_next <= aktop_int;
 526
 527                         when SWRITE_CHAR0 =>
 528                                 op1_next <= strich_int;
 529                                 opcode_next <= ALU_DIV;
 530                                 op2_next <= to_signed(10,CBITS);
 531                                 do_calc_next <= '1';
 532                         when SWRITE_CHAR1 =>
 533                                 do_calc_next <= '1';
 534                                 p_wtake_next <= '1';
 535                                 tmp := opM;
 536                                 p_write_next <= csigned2hbyte(tmp);
 537                                 wtmp_next <= op3;
 538                         when SWRITE_CHAR2 =>
 539                                 strich_next <= wtmp_int;
 540
 541                         when SWRITE_SIGN1 =>
 542                                 null;
 543                         when SWRITE_SIGN2 =>
 544                                 if z_sign_int = '1' then
 545                                         p_wtake_next <= '1';
 546                                         p_write_next <= x"2D";
 547                                 else
 548                                         assert(false) report "SWRITE_SIGN: shouldn't happen!";
 549                                 end if;
 550
 551                         when SERROR1 =>
 552                                 p_wtake_next <= '1';
 553                                 p_write_next <= hbyte(to_unsigned (character'pos(error_str(err_int)(errc_int)),8));
 554                                 errc_tmp_next <= errc_int - 1;
 555                         when SERROR2 =>
 556                                 errc_next <= errc_tmp_int;
 557
 558                         when SDONE =>
 559                                 err_next <= 0;
 560                                 errc_next <= 71;
 561                                 p_finished_next <= '1';
 562                 end case;
 563
 564                 -- fehlerbehandlung
 565                 case state_int is
 566                         when SERROR1 | SERROR2 | SDONE => null;
 567                         when others =>
 568                                 if calc_error = '1' then
 569                                         if op2_int = 0 then
 570                                                 err_next <= 1;
 571                                         else
 572                                                 err_next <= 3;
 573                                         end if;
 574                                 end if;
 575                 end case;
 576         end process;
 577 end architecture beh;