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                 -- ALU
  22                 opcode : out alu_ops;
  23                 op1 : out csigned;
  24                 op2 : out csigned;
  25                 op3 : in csigned;
  26                 do_calc : out std_logic;
  27                 calc_done : in std_logic;
  28                 calc_error : in std_logic;
  29                 -- Scanner
  30                 do_it : in std_logic;
  31                 finished : out std_logic
  32         );
  33 end entity parser;
  34
  35 architecture beh of parser is
  36         type PARSER_STATE is (SIDLE, SREAD_NEWNUMBER, SREAD_SPACE1_2,
  37         SREAD_SPACE1_3, SREAD_SPACE2, SREAD_SPACE3, SREAD_OP1, SREAD_OP2,
  38         SREAD_NEXTBYTE, SREAD_CALCNUMBER1, SREAD_CALCNUMBER2, SCALC_1, SCALC_14,
  39         SCALC_15, SCALC_2, SWRITE_CHAR1, SWRITE_CHAR2, SDONE, SERROR1, SERROR2);
  40         signal state_int, state_next : PARSER_STATE;
  41         signal z_int, z_next, strich_int, strich_next, wtmp_int, wtmp_next : csigned;
  42         signal punkt_int, punkt_next : csigned;
  43         signal rbyte_int, rbyte_next : hbyte;
  44         signal p_write_int, p_write_next : hbyte;
  45         signal p_rget_int, p_rget_next : std_logic;
  46         signal p_wtake_int, p_wtake_next : std_logic;
  47         signal p_finished_int, p_finished_next : std_logic;
  48         signal aktop_int, aktop_next : alu_ops;
  49         signal opp_int, opp_next : alu_ops;
  50         signal opcode_int, opcode_next : alu_ops;
  51         signal op1_int, op1_next : csigned;
  52         signal op2_int, op2_next : csigned;
  53         signal do_calc_int, do_calc_next : std_logic;
  54         signal goto_calcn1, goto_op1, goto_space3 : std_logic;
  55 begin
  56         p_write <= p_write_int;
  57         p_rget <= p_rget_int;
  58         p_wtake <= p_wtake_int;
  59         p_finished <= p_finished_int;
  60
  61         opcode <= opcode_int;
  62         op1 <= op1_int;
  63         op2 <= op2_int;
  64         do_calc <= do_calc_int;
  65
  66         process(sys_clk, sys_res_n)
  67         begin
  68                 if sys_res_n = '0' then
  69                         state_int <= SIDLE;
  70                         z_int <= (others => '0');
  71                         strich_int <= (others => '0');
  72                         punkt_int <= (others => '0');
  73                         wtmp_int <= (others => '0');
  74                         rbyte_int <= (others => '0');
  75                         aktop_int <= ALU_NOP;
  76                         opp_int <= ALU_NOP;
  77                         -- out ports
  78                         p_rw <= '0';
  79                         p_spalte <= (others => '0');
  80                         p_rget_int <= '0';
  81                         p_write_int <= (others => '0');
  82                         p_wtake_int <= '0';
  83                         p_finished_int <= '0';
  84                         opcode_int <= ALU_NOP;
  85                         op1_int <= (others => '0');
  86                         op2_int <= (others => '0');
  87                         do_calc_int <= '0';
  88                         finished <= '0';
  89                 elsif rising_edge(sys_clk) then
  90                         -- internal
  91                         state_int <= state_next;
  92                         z_int <= z_next;
  93                         strich_int <= strich_next;
  94                         punkt_int <= punkt_next;
  95                         wtmp_int <= wtmp_next;
  96                         rbyte_int <= rbyte_next;
  97                         aktop_int <= aktop_next;
  98                         opp_int <= opp_next;
  99                         -- out ports
 100                         p_rget_int <= p_rget_next;
 101                         p_write_int <= p_write_next;
 102                         p_wtake_int <= p_wtake_next;
 103                         p_finished_int <= p_finished_next;
 104                         opcode_int <= opcode_next;
 105                         op1_int <= op1_next;
 106                         op2_int <= op2_next;
 107                         do_calc_int <= do_calc_next;
 108                 end if;
 109         end process;
 110
 111         -- next state
 112         process(state_int, do_it, p_rdone, p_wdone, p_read, aktop_int, strich_int,
 113                 punkt_int, calc_done, wtmp_int, opp_int, goto_calcn1, goto_op1,
 114                 goto_space3)
 115         begin
 116                 state_next <= state_int;
 117
 118                 case state_int is
 119                         when SIDLE =>
 120                                 if do_it = '1' then
 121                                         state_next <= SREAD_NEWNUMBER;
 122                                 end if;
 123                         when SREAD_NEWNUMBER =>
 124                                 state_next <= SREAD_SPACE1_2;
 125                         when SREAD_SPACE1_2 =>
 126                                 if p_rdone = '1' then
 127                                         state_next <= SREAD_SPACE2;
 128                                 end if;
 129                         when SREAD_SPACE1_3 =>
 130                                 if p_rdone = '1' then
 131                                         state_next <= SREAD_SPACE3;
 132                                 end if;
 133                         when SREAD_SPACE2 | SREAD_SPACE3 =>
 134                                 if p_rdone = '0' then
 135                                         if goto_calcn1 = '0' then
 136                                                 case state_int is
 137                                                         when SREAD_SPACE2 => state_next <= SREAD_SPACE1_2;
 138                                                         when SREAD_SPACE3 => state_next <= SREAD_SPACE1_3;
 139                                                         when others => assert(false) report "wtf @ state2";
 140                                                 end case;
 141                                         end if;
 142                                 end if;
 143                                 if goto_calcn1 = '1' then
 144                                         case state_int is
 145                                                 when SREAD_SPACE2 => state_next <= SREAD_NEXTBYTE;
 146                                                 when SREAD_SPACE3 => state_next <= SREAD_OP1;
 147                                                 when others => assert(false) report "wtf @ state1";
 148                                         end case;
 149                                 end if;
 150                         when SREAD_NEXTBYTE =>
 151                                 if p_rdone = '1' then
 152                                         state_next <= SREAD_CALCNUMBER1;
 153                                 end if;
 154                         when SREAD_CALCNUMBER1 =>
 155                                 if goto_op1 = '1' then
 156                                         state_next <= SREAD_OP1;
 157                                 elsif goto_space3 = '1' then
 158                                         state_next <= SREAD_SPACE3;
 159                                 else
 160                                         state_next <= SREAD_CALCNUMBER2;
 161                                 end if;
 162                         when SREAD_OP1 =>
 163                                 state_next <= SREAD_OP2;
 164                         when SREAD_OP2 =>
 165                                 if p_rdone = '0' then
 166                                         if aktop_int /= ALU_NOP then
 167                                                 state_next <= SCALC_1;
 168                                         end if;
 169                                 end if;
 170                         when SREAD_CALCNUMBER2 =>
 171                                 if p_rdone = '0' then
 172                                         state_next <= SREAD_NEXTBYTE;
 173                                 end if;
 174                         when SCALC_1 =>
 175                                 if calc_done = '1' then
 176                                         case opp_int is
 177                                                 -- spezialfall: eine zwischenberechnung wird fuer diese
 178                                                 -- kombination benoetigt
 179                                                 when ALU_MUL | ALU_DIV =>
 180                                                         case aktop_int is
 181                                                                 when ALU_ADD | ALU_SUB | ALU_DONE => state_next <= SCALC_14;
 182                                                                 when others => state_next <= SCALC_2;
 183                                                         end case;
 184                                                 when others => state_next <= SCALC_2;
 185                                         end case;
 186                                 end if;
 187                         when SCALC_14 =>
 188                                 if calc_done = '0' then
 189                                         state_next <= SCALC_15;
 190                                 end if;
 191                         when SCALC_15 =>
 192                                 if calc_done = '1' then
 193                                         state_next <= SCALC_2;
 194                                 end if;
 195                         when SCALC_2 =>
 196                                 if aktop_int = ALU_DONE then
 197                                         state_next <= SWRITE_CHAR1;
 198                                 else
 199                                         state_next <= SREAD_NEWNUMBER;
 200                                 end if;
 201                         when SWRITE_CHAR1 =>
 202                                 if p_wdone = '1' then
 203                                         if strich_int < 10 then
 204                                                 state_next <= SDONE;
 205                                         else
 206                                                 state_next <= SWRITE_CHAR2;
 207                                         end if;
 208                                 end if;
 209                         when SERROR1 =>
 210                                 if p_wdone = '1' then
 211                                         -- TODO
 212                                         if strich_int < 10 then
 213                                                 state_next <= SDONE;
 214                                         else
 215                                                 state_next <= SWRITE_CHAR2;
 216                                         end if;
 217                                 end if;
 218                         when SWRITE_CHAR2 | SERROR2 =>
 219                                 if p_wdone = '0' then
 220                                         state_next <= SWRITE_CHAR1;
 221                                 end if;
 222                         when SDONE =>
 223                                 if p_wdone = '0' and do_it = '0' then
 224                                         state_next <= SIDLE;
 225                                 end if;
 226                 end case;
 227         end process;
 228
 229         -- out
 230         process(state_int, p_read, p_write_int, z_int, rbyte_int, p_rget_int,
 231                 strich_int, aktop_int, opp_int, opcode_int, op1_int, op2_int, op3,
 232                 do_calc_int, wtmp_int, punkt_int)
 233                 function hbyte2csigned (x : hbyte) return csigned is
 234                         variable y : csigned;
 235                 begin
 236                         case x is
 237                                 when x"30" => y := to_signed(0, CBITS);
 238                                 when x"31" => y := to_signed(1, CBITS);
 239                                 when x"32" => y := to_signed(2, CBITS);
 240                                 when x"33" => y := to_signed(3, CBITS);
 241                                 when x"34" => y := to_signed(4, CBITS);
 242                                 when x"35" => y := to_signed(5, CBITS);
 243                                 when x"36" => y := to_signed(6, CBITS);
 244                                 when x"37" => y := to_signed(7, CBITS);
 245                                 when x"38" => y := to_signed(8, CBITS);
 246                                 when x"39" => y := to_signed(9, CBITS);
 247                                 when others => assert(false) report "hbyte2csigned: shouldn't happen";
 248                         end case;
 249                         return y;
 250                 end function hbyte2csigned;
 251
 252                 function csigned2hbyte (x : csigned) return hbyte is
 253                         variable y : hbyte;
 254                 begin
 255                         case x is
 256                                 when x"00000000" => y := x"30";
 257                                 when x"00000001" => y := x"31";
 258                                 when x"00000002" => y := x"32";
 259                                 when x"00000003" => y := x"33";
 260                                 when x"00000004" => y := x"34";
 261                                 when x"00000005" => y := x"35";
 262                                 when x"00000006" => y := x"36";
 263                                 when x"00000007" => y := x"37";
 264                                 when x"00000008" => y := x"38";
 265                                 when x"00000009" => y := x"39";
 266                                 when others => assert(false) report "csigned2hbyte: shouldn't happen";
 267                         end case;
 268                         return y;
 269                 end function csigned2hbyte;
 270
 271                 variable multmp : signed(((2*CBITS)-1) downto 0);
 272                 variable tmp : csigned;
 273         begin
 274                 -- internal
 275                 z_next <= z_int;
 276                 strich_next <= strich_int;
 277                 punkt_next <= punkt_int;
 278                 wtmp_next <= wtmp_int;
 279                 rbyte_next <= rbyte_int;
 280                 aktop_next <= aktop_int;
 281                 opp_next <= opp_int;
 282                 -- signals
 283                 p_rget_next <= '0';
 284                 p_write_next <= p_write_int;
 285                 p_wtake_next <= '0';
 286                 p_finished_next <= '0';
 287                 opcode_next <= opcode_int;
 288                 op1_next <= op1_int;
 289                 op2_next <= op2_int;
 290                 do_calc_next <= '0';
 291                 goto_calcn1 <= '0';
 292                 goto_op1 <= '0';
 293                 goto_space3 <= '0';
 294
 295                 case state_int is
 296                         when SIDLE =>
 297                                 strich_next <= (others => '0');
 298                                 punkt_next <= (0 => '1', others => '0');
 299                                 opp_next <= ALU_NOP;
 300                         when SREAD_NEWNUMBER =>
 301                                 z_next <= (others => '0');
 302                                 rbyte_next <= (others => '0');
 303                                 p_write_next <= (others => '0');
 304                                 aktop_next <= ALU_NOP;
 305                         when SREAD_NEXTBYTE | SREAD_SPACE1_2 | SREAD_SPACE1_3 =>
 306                                 p_rget_next <= '1';
 307                         when SREAD_SPACE2 | SREAD_SPACE3 =>
 308                                 case p_read is
 309                                         when x"20" =>
 310                                                 null;
 311                                         when others =>
 312                                                 goto_calcn1 <= '1';
 313                                                 p_rget_next <= '1';
 314                                 end case;
 315
 316                         when SREAD_CALCNUMBER1 =>
 317                                 case p_read is
 318                                         -- '+', '-', '*', '/'
 319                                         when x"2B" | x"2D" | x"2A" | x"2F" | x"00" =>
 320                                                 goto_op1 <= '1';
 321                                                 p_rget_next <= '1';
 322
 323                                         -- ' '
 324                                         when x"20" =>
 325                                                 goto_space3 <= '1';
 326                                                 p_rget_next <= '1';
 327
 328                                         when others =>
 329                                                 -- TODO: check auf overflow
 330                                                 multmp := (z_int * 10) + hbyte2csigned(p_read);
 331                                                 z_next <= multmp((CBITS-1) downto 0);
 332                                 end case;
 333                         when SREAD_CALCNUMBER2 | SREAD_OP2 =>
 334                                 null;
 335                         when SREAD_OP1 =>
 336                                 case p_read is
 337                                         -- '+'
 338                                         when x"2B" =>
 339                                                 aktop_next <= ALU_ADD;
 340                                         -- '-'
 341                                         when x"2D" =>
 342                                                 -- TODO: sign check beim ersten byte lesen!
 343                                                 aktop_next <= ALU_SUB;
 344                                         -- '*'
 345                                         when x"2A" =>
 346                                                 aktop_next <= ALU_MUL;
 347                                         -- '/'
 348                                         when x"2F" =>
 349                                                 aktop_next <= ALU_DIV;
 350
 351                                         -- '\0'
 352                                         when x"00" =>
 353                                                 aktop_next <= ALU_DONE;
 354
 355                                         -- TODO: err!
 356                                         when others => assert(false) report "TODO: ...";
 357                                 end case;
 358
 359
 360                         when SCALC_1 =>
 361                                 case opp_int is
 362                                         when ALU_NOP | ALU_ADD | ALU_SUB =>
 363                                                 case opp_int  is
 364                                                         when ALU_SUB => op1_next <= (not z_int) + 1;
 365                                                         when others => op1_next <= z_int;
 366                                                 end case;
 367                                                 case aktop_int is
 368                                                         when ALU_ADD | ALU_SUB | ALU_DONE =>
 369                                                                 opcode_next <= ALU_ADD;
 370                                                                 op2_next <= strich_int;
 371                                                         when ALU_MUL | ALU_DIV =>
 372                                                                 opcode_next <= ALU_MUL;
 373                                                                 op2_next <= punkt_int;
 374                                                         when others => assert(false) report "SCALC_1/1: shouldn't happen!";
 375                                                 end case;
 376
 377                                         when ALU_MUL | ALU_DIV =>
 378                                                 case aktop_int is
 379                                                         when ALU_ADD | ALU_SUB | ALU_DONE | ALU_MUL | ALU_DIV =>
 380                                                                 op1_next <= punkt_int;
 381                                                                 opcode_next <= opp_int;
 382                                                                 op2_next <= z_int;
 383                                                         when others => assert(false) report "SCALC_1/2: shouldn't happen!";
 384                                                 end case;
 385                                         when others => assert(false) report "SCALC_1/3: shouldn't happen!";
 386                                 end case;
 387                                 do_calc_next <= '1';
 388
 389                         when SCALC_14 =>
 390                                 -- ueberpruefung kann man sich sparen, da diese ohnehin in
 391                                 -- nextstate gemacht wird.
 392                                 op1_next <= op3;
 393                                 do_calc_next <= '0';
 394
 395                         when SCALC_15 =>
 396                                 -- ueberpruefung kann man sich sparen, da diese ohnehin in
 397                                 -- nextstate gemacht wird.
 398                                 opcode_next <= ALU_ADD;
 399                                 op2_next <= strich_int;
 400                                 punkt_next <= (0 => '1', others => '0');
 401                                 do_calc_next <= '1';
 402
 403                         when SCALC_2 =>
 404                                 case opp_int is
 405                                         when ALU_NOP | ALU_ADD | ALU_SUB | ALU_MUL | ALU_DIV =>
 406                                                 case aktop_int is
 407                                                         when ALU_ADD | ALU_SUB | ALU_DONE =>
 408                                                                 strich_next <= op3;
 409                                                         when ALU_MUL | ALU_DIV =>
 410                                                                 punkt_next <= op3;
 411                                                         when others => assert (false) report "SCALC_2/1: shouldn't happen!";
 412                                                 end case;
 413                                         when others => assert (false) report "SCALC_2/2: shouldn't happen!";
 414                                 end case;
 415                                 -- aktuelle rechenoperation fuer naechste 'runde' uebernehmen
 416                                 opp_next <= aktop_int;
 417
 418                         when SWRITE_CHAR1 =>
 419                                 p_wtake_next <= '1';
 420                                 tmp := strich_int mod 10;
 421                                 p_write_next <= csigned2hbyte(tmp);
 422                                 wtmp_next <= strich_int / 10;
 423                         when SWRITE_CHAR2 =>
 424                                 strich_next <= wtmp_int;
 425
 426                         when SERROR1 =>
 427                                 -- TODO
 428                                 null;
 429                         when SERROR2 =>
 430                                 -- TODO
 431                                 null;
 432
 433                         when SDONE =>
 434                                 p_finished_next <= '1';
 435                 end case;
 436         end process;
 437 end architecture beh;