ISA V1.2 complete, unit tests completed, toolchain update

sy2002 · Aug 22, 2015 · 1862eba · 1862eba
1 parent 5a2885e
commit 1862eba
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Showing 9 changed files with 162 additions and 38 deletions.
diff --git a/.gitignore b/.gitignore
@@ -5,10 +5,10 @@ nexys4ddr/webtalk_impact.xml
 nexys4ddr/iseconfig
 impact.xsl
 impact_impact.xwbt
-qasm2rom
+tools/qasm2rom
 register_file.sym
-qnice
-qasm
+emulator/qnice
+tools/qasm
 *.lis
 *.out
 *.rom
diff --git a/emulator/qnice.c b/emulator/qnice.c
@@ -73,7 +73,7 @@ typedef struct statistic_data
 
 int gbl$memory[MEMORY_SIZE], gbl$registers[REGMEM_SIZE], gbl$debug = FALSE, gbl$verbose = FALSE,
     gbl$normal_operands[] = {2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2}, gbl$gather_statistics = FALSE, gbl$enable_uart = TRUE,
-    gbl$ctrl_c = FALSE;
+    gbl$ctrl_c = FALSE, gbl$breakpoint = -1;
 char *gbl$normal_mnemonics[] = {"MOVE", "ADD", "ADDC", "SUB", "SUBC", "SHL", "SHR", "SWAP", 
                                 "NOT", "AND", "OR", "XOR", "CMP", "", "HALT"},
      *gbl$branch_mnemonics[] = {"ABRA", "ASUB", "RBRA", "RSUB"}, 
@@ -550,28 +550,28 @@ int execute()
       source_1 = read_source_operand(source_mode, source_regaddr, FALSE);
       destination = source_0 + source_1;
       update_status_bits(destination, source_0, source_1, MODIFY_ALL); 
-      write_destination(destination_mode, destination_regaddr, destination, FALSE);
+      write_destination(destination_mode, destination_regaddr, destination, TRUE);
       break;
     case 2: /* ADDC */
       source_0 = read_source_operand(destination_mode, destination_regaddr, TRUE);
       source_1 = read_source_operand(source_mode, source_regaddr, FALSE);
       destination = source_0 + source_1 + ((read_register(14) >> 2) & 1); /* Take carry into account */
       update_status_bits(destination, source_0, source_1, MODIFY_ALL);
-      write_destination(destination_mode, destination_regaddr, destination, FALSE);
+      write_destination(destination_mode, destination_regaddr, destination, TRUE);
       break;
     case 3: /* SUB */
       source_0 = read_source_operand(destination_mode, destination_regaddr, TRUE);
       source_1 = read_source_operand(source_mode, source_regaddr, FALSE);
       destination = source_0 - source_1;
       update_status_bits(destination, source_0, source_1, MODIFY_ALL);
-      write_destination(destination_mode, destination_regaddr, destination, FALSE);
+      write_destination(destination_mode, destination_regaddr, destination, TRUE);
       break;
     case 4: /* SUBC */
       source_0 = read_source_operand(destination_mode, destination_regaddr, TRUE);
       source_1 = read_source_operand(source_mode, source_regaddr, FALSE);
       destination = source_0 - source_1 - ((read_register(14) >> 2) & 1); /* Take carry into account */
       update_status_bits(destination, source_0, source_1, MODIFY_ALL);
-      write_destination(destination_mode, destination_regaddr, destination, FALSE);
+      write_destination(destination_mode, destination_regaddr, destination, TRUE);
       break;
     case 5: /* SHL */
       source_0 = read_source_operand(source_mode, source_regaddr, FALSE);
@@ -612,21 +612,21 @@ int execute()
       source_1 = read_source_operand(source_mode, source_regaddr, FALSE);
       destination = source_0 & source_1;
       update_status_bits(destination, source_0, source_1, DO_NOT_MODIFY_CARRY | DO_NOT_MODIFY_OVERFLOW);
-      write_destination(destination_mode, destination_regaddr, destination, FALSE);
+      write_destination(destination_mode, destination_regaddr, destination, TRUE);
       break;
     case 10: /* OR */
       source_0 = read_source_operand(destination_mode, destination_regaddr, TRUE);
       source_1 = read_source_operand(source_mode, source_regaddr, FALSE);
       destination = source_0 | source_1;
       update_status_bits(destination, source_0, source_1, DO_NOT_MODIFY_CARRY | DO_NOT_MODIFY_OVERFLOW);
-      write_destination(destination_mode, destination_regaddr, destination, FALSE);
+      write_destination(destination_mode, destination_regaddr, destination, TRUE);
       break;
     case 11: /* XOR */
       source_0 = read_source_operand(destination_mode, destination_regaddr, TRUE);
       source_1 = read_source_operand(source_mode, source_regaddr, FALSE);
       destination = source_0 ^ source_1;
       update_status_bits(destination, source_0, source_1, DO_NOT_MODIFY_CARRY | DO_NOT_MODIFY_OVERFLOW);
-      write_destination(destination_mode, destination_regaddr, destination, FALSE);
+      write_destination(destination_mode, destination_regaddr, destination, TRUE);
       break;
     case 12: /* CMP */
       source_0 = read_source_operand(destination_mode, destination_regaddr, FALSE);
@@ -682,6 +682,13 @@ int execute()
       return TRUE;
   }
 
+  if (read_register(15) == gbl$breakpoint)
+  {
+    printf("Breakpoint reached: %04X\n", address);
+    return TRUE;
+  }
+
+
 /*  write_register(15, read_register(15) + 1); */ /* Update program counter */
   return FALSE; /* No HALT instruction executed */
 }
@@ -858,6 +865,10 @@ int main(int argc, char **argv)
     {
       if (!strcmp(token, "QUIT") || !strcmp(token, "EXIT"))
         return 0;
+      else if (!strcmp(token, "CB"))
+        gbl$breakpoint = -1;
+      else if (!strcmp(token, "SB"))
+        printf("Breakpoint set to %04X\n", gbl$breakpoint = str2int(tokenize(NULL, delimiters)));
       else if (!strcmp(token, "DUMP"))
       {
         start = str2int(tokenize(NULL, delimiters));
@@ -949,6 +960,7 @@ int main(int argc, char **argv)
       }
       else if (!strcmp(token, "HELP"))
         printf("\n\
+CB                             Clear Breakpoint\n\
 DEBUG                          Toggle debug mode (for development only)\n\
 DIS  <START>, <STOP>           Disassemble a memory region\n\
 DUMP <START>, <STOP>           Dump a memory area, START and STOP can be\n\
@@ -958,8 +970,9 @@ QUIT/EXIT                      Stop the emulator and return to the shell\n\
 RESET                          Reset the whole machine\n\
 RDUMP                          Print a register dump\n\
 RUN [<ADDR>]                   Run a program beginning at ADDR\n\
-SET <REG|ADDR> <VALUE>         Either set a register of a memory cell\n\
+SET <REG|ADDR> <VALUE>         Either set a register or a memory cell\n\
 SAVE <FILENAME> <START> <STOP> Create a loadable binary file\n\
+SB <ADDR>                      Set breakpoint to an address\n\
 STAT                           Displays some execution statistics\n\
 STEP [<ADDR>]                  Executes a single instruction at address\n\
                                ADDR. If not address is specified the current\n\

diff --git a/monitor/sysdef.asm b/monitor/sysdef.asm
@@ -22,6 +22,10 @@
 IO$BASE          .EQU 0xFC00
 IO$UART0_BASE    .EQU 0xFC00
 
+IO$TIL_BASE      .EQU 0xFF10 ; Address of TIL-display
+IO$TIL_MASK      .EQU 0xFF11 ; Mask register of TIL display
+
+
 ;
 ;  UART-registers:
 ;

diff --git a/test_programs/bram.asm b/test_programs/bram.asm
@@ -16,13 +16,17 @@ EXE_START       .EQU    0x8011              ; start address of code in RAM
                 MOVE CODE_START, R1         ; run variable for copying: source
                 MOVE EXE_START, R2          ; run variable for copying: dest
                 MOVE 1, R3                  ; we need to subtract 1 often
-                SUB R1, R0                  ; how many words to copy - 1
-                                            ; as the last opcode 2 words
+                SUB R1, R0                  ; how many words to copy
+                                            ; caution: if the last opcode
+                                            ; consists of two words, this 
+                                            ; needs to be incremented or
+                                            ; the label needs to be put one
+                                            ; line below
                 
 COPY_CODE       MOVE @R1++, @R2++           ; copy from src to dst
                 SUB R3, R0                  ; one less item to go
-                RBRA COPY_CODE, !N          ; R0 is #words-1, so check for !N
-                                            ; instead of checking for !Z
+                RBRA COPY_CODE, !N          ; R0 is decremented one time too
+                                            ; often so check for !N instead !Z
 
                 ABRA EXE_START, 1           ; execute code from RAM
 

diff --git a/test_programs/brborder.asm b/test_programs/brborder.asm
@@ -0,0 +1,77 @@
+; unit test to provoke some BRAM borderline cases
+; done by sy2002 on August, 22nd 2015
+;
+; the unit test executes correctly, if the TIL display is showing the
+; following sequence of numbers having about 1 sec delay in between
+; ABAB, CDCD, EFEF, ACDC, CCCC, ACDC, EFEF, CDCD, FFFF, .... (repeat)
+
+                .ORG 0x0000
+
+#include "../monitor/sysdef.asm"                
+
+RAMEXE          .EQU 0x8000
+VARIABLE1       .EQU 0x80E0
+STACK           .EQU 0x80FF
+
+                MOVE STACK, SP
+                MOVE IO$TIL_BASE, R12
+
+                ; copy part of the logic to RAM
+                MOVE TORAM_END, R8
+                SUB TORAM_START, R8
+                MOVE TORAM_START, R9
+                MOVE RAMEXE, R10
+                ASUB COPY_CODE, 1
+
+                ; create the first two numbers of the seq: ABAB and CDCD
+                MOVE VARIABLE1, R0
+                MOVE 0xABAB, @R0
+                MOVE @R0++, R1
+                MOVE 0xCDCD, @R0
+                MOVE @R0++, R2
+
+                ; create EFEF, ACDC, ACDC, EFEF, CDCD, FFFF
+                ; note that the "CCCC" is inserted in the display routine
+                ASUB RAMEXE, 1
+
+CONT_IN_ROM     MOVE R1, @R12
+                ASUB WAIT_A_SEC, 1
+                MOVE R2, @R12
+                ASUB WAIT_A_SEC, 1
+                MOVE R3, @R12
+                ASUB WAIT_A_SEC, 1
+                MOVE R4, @R12
+                ASUB WAIT_A_SEC, 1
+                MOVE 0xCCCC, @R12
+                ASUB WAIT_A_SEC, 1
+                MOVE R5, @R12
+                ASUB WAIT_A_SEC, 1
+                MOVE R6, @R12
+                ASUB WAIT_A_SEC, 1
+                MOVE R7, @R12
+                ASUB WAIT_A_SEC, 1
+                MOVE R11, @R12
+                ASUB WAIT_A_SEC, 1
+                ABRA CONT_IN_ROM, 1
+
+TORAM_START     MOVE 0xEFEF, @R0
+                MOVE @R0++, R3
+                MOVE 0xACDC, @R0
+                MOVE @R0, R4
+
+                MOVE R4, R5
+                MOVE @--R0, R6
+                MOVE @--R0, R7
+
+                ; intentionally strange to trigger some bram async reset
+                MOVE @--R0, R11
+                MOVE R0, R10
+                MOVE R11, @R0++
+                MOVE 0x5454, @R0
+                MOVE @R0, @R0
+                ADD @R10, @R0
+                MOVE @R0, R11
+                RET
+TORAM_END       .BLOCK 1
+
+#include "debug_tools.asm"
diff --git a/test_programs/debug_tools.asm b/test_programs/debug_tools.asm
@@ -0,0 +1,37 @@
+; utility routines for debugging
+; sysdef.asm needs to be included before this
+; done by sy2002 in August 2015
+
+; copy code from one memory destination (e.g. ROM) to another (e.g. RAM)
+; R8: amount of instruction words to copy
+; R9: src, R10: dst
+;
+; CAUTION FOR R8: if the last opcode consists of two words, then better
+; place the label one line later, e.g. to a .BLOCK 1 statement, otherwise
+; the second word of the last opcode will not be copied
+
+COPY_CODE       MOVE @R9++, @R10++          ; copy from src to dst
+                SUB 1, R8                   ; one less item to go
+                RBRA COPY_CODE, !N          ; R0 is decremented one time too
+                                            ; much, so check for !N instead of
+                                            ; checking for !Z
+                RET                         ; return from sub routine
+
+; sub routine to wait for about 1 second (assuming a ~10 MIPS operation)
+
+WAIT_A_SEC      MOVE    0x1388, R8          ; inner wait cycles: 5.000 decimal
+                MOVE    0x09C4, R9          ; outer wait cycles: 2.500 decimal
+                RSUB    WAIT_A_WHILE, 1     ; wait
+                RET                         ; return from sub routine
+
+; sub routine to wait for R8 x R9 cycles
+
+WAIT_A_WHILE    INCRB                       ; next register bank
+                MOVE    R9, R1              ; outer wait cycles
+WAS_WAIT_LOOP2  MOVE    R8, R0              ; inner wait cycles
+WAS_WAIT_LOOP1  SUB     1, R0               ; dec inner wait cycles and ...
+                RBRA    WAS_WAIT_LOOP1, !Z  ; ... repeat if not zero
+                SUB     1, R1               ; dec outer wait cycles and ...
+                RBRA    WAS_WAIT_LOOP2, !Z  ; ... repeat if not zero
+                DECRB                       ; restore previous register bank
+                RET                         ; return from sub routine
diff --git a/tools/qasm.c b/tools/qasm.c
@@ -548,16 +548,16 @@ int decode_operand(char *operand, int *op_code)
 */
 int assemble()
 {
-  int opcode, type, line_counter, address, i, error_counter = 0, number_of_operands, negate, flag, value, size,
-    special_char;
+  int opcode, type, line_counter, address = 0, i, error_counter = 0, number_of_operands, negate, flag, value, size,
+    special_char, org_found = 0;
   char line[STRING_LENGTH], *p, *delimiters = " ,", *token, *sr_bits = "1XCZNVIM";
   data_structure *entry;
 
   /* First pass: */
 #ifdef DEBUG
   printf("assemble: Starting first pass.\n");
 #endif
-  for (address = line_counter = 1, entry = gbl$data; entry; entry = entry->next, line_counter++)
+  for (line_counter = 1, entry = gbl$data; entry; entry = entry->next, line_counter++)
   {
     strcpy(line, entry->source);           /* Get a local copy of the line and clean it up */
     entry->state = STATE$NOTHING_YET_DONE; /* Still a lot to do */

diff --git a/vhdl/env1_globals.vhd b/vhdl/env1_globals.vhd
@@ -10,8 +10,8 @@ use IEEE.STD_LOGIC_1164.all;
 package env1_globals is
 
 -- file name and file size (in lines) of the file that is converted to the ROM located at 0x0000
-constant ROM_FILE             : string    := "../test_programs/bram.rom";
-constant ROM_SIZE             : integer   := 38;
+constant ROM_FILE             : string    := "../test_programs/brborder.rom";
+constant ROM_SIZE             : integer   := 101;
 
 -- size of lower register bank: should be 256
 -- set to 16 during development for faster synthesis, routing, etc.

diff --git a/vhdl/qnice_cpu.vhd b/vhdl/qnice_cpu.vhd
@@ -190,6 +190,12 @@ signal Alu_V               : std_logic;
 
 begin
 
+-- @TODO (priority 2): Completely re-do the Tristate buffer topic. The lenghty wait-state and the #0000 situation when
+-- writing are not necessary! As we have enough flip-flops, the Tristate handling can be done in "real-time".
+-- as this has probably some pretty far reaching impact, the question is when to implement this. On the other hand,
+-- the longer we wait, the bigger the impact will be. Some analysis with some MOVE, ADD & Co indirect @memory read/write
+-- scenario will for sure help and create a more clear view.
+
    -- TriState buffer/driver for the 16 bit DATA bus
    DATA_driver : TriState_Buffer
       generic map
@@ -335,23 +341,6 @@ begin
             fsmNextCpuState <= cs_std_seq;
             fsmInstruction <= (others => '0');
 
--- BTW: as soon as all this works, plus some more unit tests especially for some to be found complicated BRAM borderline
--- cases (e.g. ADD @R1, @R2, everything in RAM plus before and after some instructions that challenge the asyncreset),
--- I should checkin the ISA V1.2 docu PDF (create a qnice/doc folder)
--- check in the current assembler and stuff (inside the qnice folder), the emulator (within qnice folder, and the other
--- material from there) and call it "V1.0" (before nerd session), because this is then a fully fledged 
--- QNICE CPU working in the initival ENV1 scenario. V1.1 could then be: plus UART plus Bernd's monitor is running.
--- Later, V2.0 might be the new ISA plus another scenario than env1, e.g. QBM-1.
--- the tagging in GIT/GITHUB is important, so that in a later "retro" session, we can compare ISA 1.2 in env1 with
--- a full "QBM-1" computer having the new ISA (e.g. new CMP command, etc.).
--- Update all tools in qnice folder to vaxman's latest material from SourceForge.
-
--- @TODO (priority 2): Completely re-do the Tristate buffer topic. The lenghty wait-state and the #0000 situation when
--- writing are not necessary! As we have enough flip-flops, the Tristate handling can be done in "real-time".
--- as this has probably some pretty far reaching impact, the question is when to implement this. On the other hand,
--- the longer we wait, the bigger the impact will be. Some analysis with some MOVE, ADD & Co indirect @memory read/write
--- scenario will for sure help and create a more clear view.
-
          -- as the previous state sets the direction control to read and the address to a meaningful value
          -- (i.e. 0 after cs_reset or current PC afterwards), the DATA_driver will take care, that at the
          -- falling edge of cs_fetch's clock cycle, DATA_From_Bus will contain the next opcode