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[/] [eco32/] [tags/] [eco32-0.22/] [monitor/] [monitor/] [command.c] - Blame information for rev 138

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/*
 * command.c -- command interpreter
 */
 
 
#include "common.h"
#include "stdarg.h"
#include "romlib.h"
#include "getline.h"
#include "command.h"
#include "asm.h"
#include "disasm.h"
#include "boot.h"
#include "cpu.h"
#include "mmu.h"
#include "start.h"
 
 
#define MAX_TOKENS      10
 
 
typedef struct {
  char *name;
  void (*hlpProc)(void);
  void (*cmdProc)(char *tokens[], int n);
} Command;
 
extern Command commands[];
extern int numCommands;
 
 
static void help(void) {
  printf("valid commands are:\n");
  printf("  help    get help\n");
  printf("  +       add and subtract\n");
  printf("  a       assemble\n");
  printf("  u       unassemble\n");
  printf("  b       set/reset breakpoint\n");
  printf("  c       continue from breakpoint\n");
  printf("  s       single-step\n");
  printf("  @       show/set PC\n");
  printf("  p       show/set PSW\n");
  printf("  r       show/set register\n");
  printf("  d       dump memory\n");
  printf("  mw      show/set memory word\n");
  printf("  mh      show/set memory halfword\n");
  printf("  mb      show/set memory byte\n");
  printf("  t       show/set TLB contents\n");
  printf("  boot    bootstrap from disk\n");
  printf("type 'help <cmd>' to get help for <cmd>\n");
}
 
 
static void help00(void) {
  printf("  help              show a list of commands\n");
  printf("  help <cmd>        show help for <cmd>\n");
}
 
 
static void help01(void) {
  printf("  +  <num1> <num2>  add and subtract <num1> and <num2>\n");
}
 
 
static void help02(void) {
  printf("  a                 assemble starting at PC\n");
  printf("  a  <addr>         assemble starting at <addr>\n");
}
 
 
static void help03(void) {
  printf("  u                 unassemble 16 instrs starting at PC\n");
  printf("  u  <addr>         unassemble 16 instrs starting at <addr>\n");
  printf("  u  <addr> <cnt>   unassemble <cnt> instrs starting at <addr>\n");
}
 
 
static void help04(void) {
  printf("  b                 reset break\n");
  printf("  b  <addr>         set break at <addr>\n");
}
 
 
static void help05(void) {
  printf("  c                 continue execution\n");
  printf("  c  <cnt>          continue execution <cnt> times\n");
}
 
 
static void help06(void) {
  printf("  s                 single-step one instruction\n");
  printf("  s  <cnt>          single-step <cnt> instructions\n");
}
 
 
static void help07(void) {
  printf("  @                 show PC\n");
  printf("  @  <addr>         set PC to <addr>\n");
}
 
 
static void help08(void) {
  printf("  p                 show PSW\n");
  printf("  p  <data>         set PSW to <data>\n");
}
 
 
static void help09(void) {
  printf("  r                 show all registers\n");
  printf("  r  <reg>          show register <reg>\n");
  printf("  r  <reg> <data>   set register <reg> to <data>\n");
}
 
 
static void help10(void) {
  printf("  d                 dump 256 bytes starting at PC\n");
  printf("  d  <addr>         dump 256 bytes starting at <addr>\n");
  printf("  d  <addr> <cnt>   dump <cnt> bytes starting at <addr>\n");
}
 
 
static void help11(void) {
  printf("  mw                show memory word at PC\n");
  printf("  mw <addr>         show memory word at <addr>\n");
  printf("  mw <addr> <data>  set memory word at <addr> to <data>\n");
}
 
 
static void help12(void) {
  printf("  mh                show memory halfword at PC\n");
  printf("  mh <addr>         show memory halfword at <addr>\n");
  printf("  mh <addr> <data>  set memory halfword at <addr> to <data>\n");
}
 
 
static void help13(void) {
  printf("  mb                show memory byte at PC\n");
  printf("  mb <addr>         show memory byte at <addr>\n");
  printf("  mb <addr> <data>  set memory byte at <addr> to <data>\n");
}
 
 
static void help14(void) {
  printf("  t                 show TLB contents\n");
  printf("  t  <i>            show TLB contents at <i>\n");
  printf("  t  <i> p <data>   set TLB contents at <i> to page <data>\n");
  printf("  t  <i> f <data>   set TLB contents at <i> to frame <data>\n");
}
 
 
static void help15(void) {
  printf("  boot <n>          load and execute first sector of disk <n>\n");
}
 
 
static Bool getHexNumber(char *str, Word *valptr) {
  char *end;
 
  *valptr = strtoul(str, &end, 16);
  return *end == '\0';
}
 
 
static Bool getDecNumber(char *str, int *valptr) {
  char *end;
 
  *valptr = strtoul(str, &end, 10);
  return *end == '\0';
}
 
 
static void showPC(void) {
  Word pc, psw;
  Word instr;
 
  pc = cpuGetPC();
  psw = cpuGetPSW();
  instr = mmuReadWord(pc);
  printf("PC   %08X     [PC]   %08X   %s\n",
         pc, instr, disasm(instr, pc));
}
 
 
static void showBreak(void) {
  Word brk;
 
  brk = cpuGetBreak();
  printf("Brk  ");
  if (cpuTestBreak()) {
    printf("%08X", brk);
  } else {
    printf("--------");
  }
  printf("\n");
}
 
 
static void showPSW(void) {
  Word psw;
  int i;
 
  psw = cpuGetPSW();
  printf("     xxxx  V  UPO  IPO  IACK   MASK\n");
  printf("PSW  ");
  for (i = 31; i >= 0; i--) {
    if (i == 27 || i == 26 || i == 23 || i == 20 || i == 15) {
      printf("  ");
    }
    printf("%c", psw & (1 << i) ? '1' : '0');
  }
  printf("\n");
}
 
 
static void doHelp(char *tokens[], int n) {
  int i;
 
  if (n == 1) {
    help();
  } else if (n == 2) {
    for (i = 0; i < numCommands; i++) {
      if (strcmp(commands[i].name, tokens[1]) == 0) {
        (*commands[i].hlpProc)();
        return;
      }
    }
    printf("no help available for '%s', sorry\n", tokens[1]);
  } else {
    help00();
  }
}
 
 
static void doArith(char *tokens[], int n) {
  Word num1, num2, num3, num4;
 
  if (n == 3) {
    if (!getHexNumber(tokens[1], &num1)) {
      printf("illegal first number\n");
      return;
    }
    if (!getHexNumber(tokens[2], &num2)) {
      printf("illegal second number\n");
      return;
    }
    num3 = num1 + num2;
    num4 = num1 - num2;
    printf("add = %08X, sub = %08X\n", num3, num4);
  } else {
    help01();
  }
}
 
 
static void doAssemble(char *tokens[], int n) {
  Word addr;
  Word psw;
  char prompt[30];
  char *line;
  char *msg;
  Word instr;
 
  if (n == 1) {
    addr = cpuGetPC();
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
  } else {
    help02();
    return;
  }
  addr &= ~0x00000003;
  psw = cpuGetPSW();
  while (1) {
    sprintf(prompt, "ASM @ %08X: ", addr);
    line = getLine(prompt);
    if (*line == '\0' || *line == '\n') {
      break;
    }
    addHist(line);
    msg = asmInstr(line, addr, &instr);
    if (msg != NULL) {
      printf("%s\n", msg);
    } else {
      mmuWriteWord(addr, instr);
      addr += 4;
    }
  }
}
 
 
static void doUnassemble(char *tokens[], int n) {
  Word addr, count;
  Word psw;
  int i;
  Word instr;
 
  if (n == 1) {
    addr = cpuGetPC();
    count = 16;
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    count = 16;
  } else if (n == 3) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    if (!getHexNumber(tokens[2], &count)) {
      printf("illegal count\n");
      return;
    }
    if (count == 0) {
      return;
    }
  } else {
    help03();
    return;
  }
  addr &= ~0x00000003;
  psw = cpuGetPSW();
  for (i = 0; i < count; i++) {
    instr = mmuReadWord(addr);
    printf("%08X:  %08X    %s\n",
            addr, instr, disasm(instr, addr));
    if (addr + 4 < addr) {
      /* wrap-around */
      break;
    }
    addr += 4;
  }
}
 
 
static void doBreak(char *tokens[], int n) {
  Word addr;
 
  if (n == 1) {
    cpuResetBreak();
    showBreak();
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    addr &= ~0x00000003;
    cpuSetBreak(addr);
    showBreak();
  } else {
    help04();
  }
}
 
 
static void doContinue(char *tokens[], int n) {
  Word count, i;
  Word addr;
 
  if (n == 1) {
    count = 1;
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &count) || count == 0) {
      printf("illegal count\n");
      return;
    }
  } else {
    help05();
    return;
  }
  for (i = 0; i < count; i++) {
    cpuRun();
  }
  addr = cpuGetPC();
  printf("Break at %08X\n", addr);
  showPC();
}
 
 
static void doStep(char *tokens[], int n) {
  Word count, i;
 
  if (n == 1) {
    count = 1;
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &count) || count == 0) {
      printf("illegal count\n");
      return;
    }
  } else {
    help06();
    return;
  }
  for (i = 0; i < count; i++) {
    cpuStep();
  }
  showPC();
}
 
 
static void doPC(char *tokens[], int n) {
  Word addr;
 
  if (n == 1) {
    showPC();
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    addr &= ~0x00000003;
    cpuSetPC(addr);
    showPC();
  } else {
    help07();
  }
}
 
 
static void explainPSW(Word data) {
  int i;
 
  printf("interrupt vector                   : %s (%s)\n",
         data & PSW_V ? "on " : "off",
         data & PSW_V ? "RAM" : "ROM");
  printf("current user mode                  : %s (%s)\n",
         data & PSW_UM ? "on " : "off",
         data & PSW_UM ? "user" : "kernel");
  printf("previous user mode                 : %s (%s)\n",
         data & PSW_PUM ? "on " : "off",
         data & PSW_PUM ? "user" : "kernel");
  printf("old user mode                      : %s (%s)\n",
         data & PSW_OUM ? "on " : "off",
         data & PSW_OUM ? "user" : "kernel");
  printf("current interrupt enable           : %s (%s)\n",
         data & PSW_IE ? "on " : "off",
         data & PSW_IE ? "enabled" : "disabled");
  printf("previous interrupt enable          : %s (%s)\n",
         data & PSW_PIE ? "on " : "off",
         data & PSW_PIE ? "enabled" : "disabled");
  printf("old interrupt enable               : %s (%s)\n",
         data & PSW_OIE ? "on " : "off",
         data & PSW_OIE ? "enabled" : "disabled");
  printf("last interrupt acknowledged        : %02X  (%s)\n",
         (data & PSW_PRIO_MASK) >> 16,
         exceptionToString((data & PSW_PRIO_MASK) >> 16));
  for (i = 15; i >= 0; i--) {
    printf("%-35s: %s (%s)\n",
           exceptionToString(i),
           data & (1 << i) ? "on " : "off",
           data & (1 << i) ? "enabled" : "disabled");
  }
}
 
 
static void doPSW(char *tokens[], int n) {
  Word data;
 
  if (n == 1) {
    data = cpuGetPSW();
    showPSW();
    explainPSW(data);
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &data)) {
      printf("illegal data\n");
      return;
    }
    data &= 0x0FFFFFFF;
    cpuSetPSW(data);
    showPSW();
    explainPSW(data);
  } else {
    help08();
  }
}
 
 
static void doRegister(char *tokens[], int n) {
  int i, j;
  int reg;
  Word data;
 
  if (n == 1) {
    for (i = 0; i < 8; i++) {
      for (j = 0; j < 4; j++) {
        reg = 8 * j + i;
        data = cpuGetReg(reg);
        printf("$%-2d  %08X     ", reg, data);
      }
      printf("\n");
    }
    showPSW();
    showBreak();
    showPC();
  } else if (n == 2) {
    if (!getDecNumber(tokens[1], &reg) || reg < 0 || reg >= 32) {
      printf("illegal register number\n");
      return;
    }
    data = cpuGetReg(reg);
    printf("$%-2d  %08X\n", reg, data);
  } else if (n == 3) {
    if (!getDecNumber(tokens[1], &reg) || reg < 0 || reg >= 32) {
      printf("illegal register number\n");
      return;
    }
    if (!getHexNumber(tokens[2], &data)) {
      printf("illegal data\n");
      return;
    }
    cpuSetReg(reg, data);
  } else {
    help09();
  }
}
 
 
static void doDump(char *tokens[], int n) {
  Word addr, count;
  Word psw;
  Word lo, hi, curr;
  int lines, i, j;
  Word tmp;
  Byte c;
 
  if (n == 1) {
    addr = cpuGetPC();
    count = 16 * 16;
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    count = 16 * 16;
  } else if (n == 3) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    if (!getHexNumber(tokens[2], &count)) {
      printf("illegal count\n");
      return;
    }
    if (count == 0) {
      return;
    }
  } else {
    help10();
    return;
  }
  psw = cpuGetPSW();
  lo = addr & ~0x0000000F;
  hi = addr + count - 1;
  if (hi < lo) {
    /* wrap-around */
    hi = 0xFFFFFFFF;
  }
  lines = (hi - lo + 16) >> 4;
  curr = lo;
  for (i = 0; i < lines; i++) {
    printf("%08X:  ", curr);
    for (j = 0; j < 16; j++) {
      tmp = curr + j;
      if (tmp < addr || tmp > hi) {
        printf("  ");
      } else {
        c = mmuReadByte(tmp);
        printf("%02X", c);
      }
      printf(" ");
    }
    printf("  ");
    for (j = 0; j < 16; j++) {
      tmp = curr + j;
      if (tmp < addr || tmp > hi) {
        printf(" ");
      } else {
        c = mmuReadByte(tmp);
        if (c >= 32 && c <= 126) {
          printf("%c", c);
        } else {
          printf(".");
        }
      }
    }
    printf("\n");
    curr += 16;
  }
}
 
 
static void doMemoryWord(char *tokens[], int n) {
  Word psw;
  Word addr;
  Word data;
  Word tmpData;
 
  psw = cpuGetPSW();
  if (n == 1) {
    addr = cpuGetPC();
    data = mmuReadWord(addr);
    printf("%08X:  %08X\n", addr, data);
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    data = mmuReadWord(addr);
    printf("%08X:  %08X\n", addr, data);
  } else if (n == 3) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    if (!getHexNumber(tokens[2], &tmpData)) {
      printf("illegal data\n");
      return;
    }
    data = tmpData;
    mmuWriteWord(addr, data);
  } else {
    help11();
  }
}
 
 
static void doMemoryHalf(char *tokens[], int n) {
  Word psw;
  Word addr;
  Half data;
  Word tmpData;
 
  psw = cpuGetPSW();
  if (n == 1) {
    addr = cpuGetPC();
    data = mmuReadHalf(addr);
    printf("%08X:  %04X\n", addr, data);
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    data = mmuReadHalf(addr);
    printf("%08X:  %04X\n", addr, data);
  } else if (n == 3) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    if (!getHexNumber(tokens[2], &tmpData)) {
      printf("illegal data\n");
      return;
    }
    data = (Half) tmpData;
    mmuWriteHalf(addr, data);
  } else {
    help12();
  }
}
 
 
static void doMemoryByte(char *tokens[], int n) {
  Word psw;
  Word addr;
  Byte data;
  Word tmpData;
 
  psw = cpuGetPSW();
  if (n == 1) {
    addr = cpuGetPC();
    data = mmuReadByte(addr);
    printf("%08X:  %02X\n", addr, data);
  } else if (n == 2) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    data = mmuReadByte(addr);
    printf("%08X:  %02X\n", addr, data);
  } else if (n == 3) {
    if (!getHexNumber(tokens[1], &addr)) {
      printf("illegal address\n");
      return;
    }
    if (!getHexNumber(tokens[2], &tmpData)) {
      printf("illegal data\n");
      return;
    }
    data = (Byte) tmpData;
    mmuWriteByte(addr, data);
  } else {
    help13();
  }
}
 
 
static void doTLB(char *tokens[], int n) {
  int index;
  TLB_Entry tlbEntry;
  Word data;
 
  if (n == 1) {
    for (index = 0; index < TLB_SIZE; index++) {
      tlbEntry = mmuGetTLB(index);
      printf("TLB[%02d]    page  %08X    frame  %08X  %c  %c\n",
             index, tlbEntry.page, tlbEntry.frame,
             tlbEntry.write ? 'w' : '-',
             tlbEntry.valid ? 'v' : '-');
    }
    printf("Index(1)   %08X\n", mmuGetIndex());
    printf("EntryHi(2) %08X\n", mmuGetEntryHi());
    printf("EntryLo(3) %08X\n", mmuGetEntryLo());
  } else if (n == 2) {
    if (!getDecNumber(tokens[1], &index) || index < 0 || index >= TLB_SIZE) {
      printf("illegal TLB index\n");
      return;
    }
    tlbEntry = mmuGetTLB(index);
    printf("TLB[%02d]    page  %08X    frame  %08X  %c  %c\n",
           index, tlbEntry.page, tlbEntry.frame,
           tlbEntry.write ? 'w' : '-',
           tlbEntry.valid ? 'v' : '-');
  } else if (n == 3) {
    help14();
  } else if (n == 4) {
    if (!getDecNumber(tokens[1], &index) || index < 0 || index >= TLB_SIZE) {
      printf("illegal TLB index\n");
      return;
    }
    if (!getHexNumber(tokens[3], &data)) {
      printf("illegal data\n");
      return;
    }
    tlbEntry = mmuGetTLB(index);
    if (strcmp(tokens[2], "p") == 0) {
      tlbEntry.page = data & PAGE_MASK;
    } else
    if (strcmp(tokens[2], "f") == 0) {
      tlbEntry.frame = data & PAGE_MASK;
      tlbEntry.write = data & TLB_WRITE ? true : false;
      tlbEntry.valid = data & TLB_VALID ? true : false;
    } else {
      printf("TLB selector is not one of 'p' or 'f'\n");
      return;
    }
    mmuSetTLB(index, tlbEntry);
    printf("TLB[%02d]    page  %08X    frame  %08X  %c  %c\n",
           index, tlbEntry.page, tlbEntry.frame,
           tlbEntry.write ? 'w' : '-',
           tlbEntry.valid ? 'v' : '-');
  } else {
    help14();
  }
}
 
 
static void doBoot(char *tokens[], int n) {
  int dskno;
 
  if (n == 2) {
    if (!getDecNumber(tokens[1], &dskno) || dskno < 0 || dskno > 1) {
      printf("illegal disk number\n");
      return;
    }
    boot(dskno);
  } else {
    help15();
  }
}
 
 
Command commands[] = {
  { "help", help00, doHelp       },
  { "+",    help01, doArith      },
  { "a",    help02, doAssemble   },
  { "u",    help03, doUnassemble },
  { "b",    help04, doBreak      },
  { "c",    help05, doContinue   },
  { "s",    help06, doStep       },
  { "@",    help07, doPC         },
  { "p",    help08, doPSW        },
  { "r",    help09, doRegister   },
  { "d",    help10, doDump       },
  { "mw",   help11, doMemoryWord },
  { "mh",   help12, doMemoryHalf },
  { "mb",   help13, doMemoryByte },
  { "t",    help14, doTLB        },
  { "boot", help15, doBoot       },
};
 
int numCommands = sizeof(commands) / sizeof(commands[0]);
 
 
static void doCommand(char *line) {
  char *tokens[MAX_TOKENS];
  int n;
  char *p;
  int i;
 
  n = 0;
  p = strtok(line, " \t\n");
  while (p != NULL) {
    if (n == MAX_TOKENS) {
      printf("too many tokens on line\n");
      return;
    }
    tokens[n++] = p;
    p = strtok(NULL, " \t\n");
  }
  if (n == 0) {
    return;
  }
  for (i = 0; i < numCommands; i++) {
    if (strcmp(commands[i].name, tokens[0]) == 0) {
      (*commands[i].cmdProc)(tokens, n);
      return;
    }
  }
  help();
}
 
 
static char *article(char firstLetterOfNoun) {
  switch (firstLetterOfNoun) {
    case 'a':
    case 'e':
    case 'i':
    case 'o':
    case 'u':
      return "An";
    default:
      return "A";
  }
}
 
 
static void interactiveException(int exception) {
  char *what;
 
  what = exceptionToString(exception);
  printf("\n");
  printf("NOTE: %s %s occurred while executing the command.\n",
         article(*what), what);
  printf("      This event will not alter the state of the CPU.\n");
}
 
 
void execCommand(char *line) {
  MonitorState commandState;
 
  if (saveState(&commandState)) {
    /* initialization */
    monitorReturn = &commandState;
    doCommand(line);
  } else {
    /* an exception was thrown */
    interactiveException((userContext.psw & PSW_PRIO_MASK) >> 16);
  }
  monitorReturn = NULL;
}

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[/] [eco32/] [tags/] [eco32-0.22/] [monitor/] [monitor/] [command.c] - Blame information for rev 138

Line No.	Rev	Author	Line
1	16	hellwig	`/*`
2			`* command.c -- command interpreter`
3			`*/`
4
5
6			`#include "common.h"`
7			`#include "stdarg.h"`
8			`#include "romlib.h"`
9			`#include "getline.h"`
10			`#include "command.h"`
11			`#include "asm.h"`
12			`#include "disasm.h"`
13			`#include "boot.h"`
14			`#include "cpu.h"`
15			`#include "mmu.h"`
16			`#include "start.h"`
17
18
19			`#define MAX_TOKENS 10`
20
21
22			`typedef struct {`
23			`char *name;`
24			`void (*hlpProc)(void);`
25			`void (cmdProc)(char tokens[], int n);`
26			`} Command;`
27
28			`extern Command commands[];`
29			`extern int numCommands;`
30
31
32			`static void help(void) {`
33			`printf("valid commands are:\n");`
34			`printf(" help get help\n");`
35			`printf(" + add and subtract\n");`
36			`printf(" a assemble\n");`
37			`printf(" u unassemble\n");`
38			`printf(" b set/reset breakpoint\n");`
39			`printf(" c continue from breakpoint\n");`
40			`printf(" s single-step\n");`
41			`printf(" @ show/set PC\n");`
42			`printf(" p show/set PSW\n");`
43			`printf(" r show/set register\n");`
44			`printf(" d dump memory\n");`
45			`printf(" mw show/set memory word\n");`
46			`printf(" mh show/set memory halfword\n");`
47			`printf(" mb show/set memory byte\n");`
48			`printf(" t show/set TLB contents\n");`
49			`printf(" boot bootstrap from disk\n");`
50			`printf("type 'help <cmd>' to get help for <cmd>\n");`
51			`}`
52
53
54			`static void help00(void) {`
55			`printf(" help show a list of commands\n");`
56			`printf(" help <cmd> show help for <cmd>\n");`
57			`}`
58
59
60			`static void help01(void) {`
61			`printf(" + <num1> <num2> add and subtract <num1> and <num2>\n");`
62			`}`
63
64
65			`static void help02(void) {`
66			`printf(" a assemble starting at PC\n");`
67			`printf(" a <addr> assemble starting at <addr>\n");`
68			`}`
69
70
71			`static void help03(void) {`
72			`printf(" u unassemble 16 instrs starting at PC\n");`
73			`printf(" u <addr> unassemble 16 instrs starting at <addr>\n");`
74			`printf(" u <addr> <cnt> unassemble <cnt> instrs starting at <addr>\n");`
75			`}`
76
77
78			`static void help04(void) {`
79			`printf(" b reset break\n");`
80			`printf(" b <addr> set break at <addr>\n");`
81			`}`
82
83
84			`static void help05(void) {`
85			`printf(" c continue execution\n");`
86			`printf(" c <cnt> continue execution <cnt> times\n");`
87			`}`
88
89
90			`static void help06(void) {`
91			`printf(" s single-step one instruction\n");`
92			`printf(" s <cnt> single-step <cnt> instructions\n");`
93			`}`
94
95
96			`static void help07(void) {`
97			`printf(" @ show PC\n");`
98			`printf(" @ <addr> set PC to <addr>\n");`
99			`}`
100
101
102			`static void help08(void) {`
103			`printf(" p show PSW\n");`
104			`printf(" p <data> set PSW to <data>\n");`
105			`}`
106
107
108			`static void help09(void) {`
109			`printf(" r show all registers\n");`
110			`printf(" r <reg> show register <reg>\n");`
111			`printf(" r <reg> <data> set register <reg> to <data>\n");`
112			`}`
113
114
115			`static void help10(void) {`
116			`printf(" d dump 256 bytes starting at PC\n");`
117			`printf(" d <addr> dump 256 bytes starting at <addr>\n");`
118			`printf(" d <addr> <cnt> dump <cnt> bytes starting at <addr>\n");`
119			`}`
120
121
122			`static void help11(void) {`
123			`printf(" mw show memory word at PC\n");`
124			`printf(" mw <addr> show memory word at <addr>\n");`
125			`printf(" mw <addr> <data> set memory word at <addr> to <data>\n");`
126			`}`
127
128
129			`static void help12(void) {`
130			`printf(" mh show memory halfword at PC\n");`
131			`printf(" mh <addr> show memory halfword at <addr>\n");`
132			`printf(" mh <addr> <data> set memory halfword at <addr> to <data>\n");`
133			`}`
134
135
136			`static void help13(void) {`
137			`printf(" mb show memory byte at PC\n");`
138			`printf(" mb <addr> show memory byte at <addr>\n");`
139			`printf(" mb <addr> <data> set memory byte at <addr> to <data>\n");`
140			`}`
141
142
143			`static void help14(void) {`
144			`printf(" t show TLB contents\n");`
145			`printf(" t <i> show TLB contents at <i>\n");`
146			`printf(" t <i> p <data> set TLB contents at <i> to page <data>\n");`
147			`printf(" t <i> f <data> set TLB contents at <i> to frame <data>\n");`
148			`}`
149
150
151			`static void help15(void) {`
152			`printf(" boot <n> load and execute first sector of disk <n>\n");`
153			`}`
154
155
156			`static Bool getHexNumber(char str, Word valptr) {`
157			`char *end;`
158
159			`*valptr = strtoul(str, &end, 16);`
160			`return *end == '\0';`
161			`}`
162
163
164			`static Bool getDecNumber(char str, int valptr) {`
165			`char *end;`
166
167			`*valptr = strtoul(str, &end, 10);`
168			`return *end == '\0';`
169			`}`
170
171
172			`static void showPC(void) {`
173			`Word pc, psw;`
174			`Word instr;`
175
176			`pc = cpuGetPC();`
177			`psw = cpuGetPSW();`
178			`instr = mmuReadWord(pc);`
179			`printf("PC %08X [PC] %08X %s\n",`
180			`pc, instr, disasm(instr, pc));`
181			`}`
182
183
184			`static void showBreak(void) {`
185			`Word brk;`
186
187			`brk = cpuGetBreak();`
188			`printf("Brk ");`
189			`if (cpuTestBreak()) {`
190			`printf("%08X", brk);`
191			`} else {`
192			`printf("--------");`
193			`}`
194			`printf("\n");`
195			`}`
196
197
198			`static void showPSW(void) {`
199			`Word psw;`
200			`int i;`
201
202			`psw = cpuGetPSW();`
203			`printf(" xxxx V UPO IPO IACK MASK\n");`
204			`printf("PSW ");`
205			`for (i = 31; i >= 0; i--) {`
206			`if (i == 27 \|\| i == 26 \|\| i == 23 \|\| i == 20 \|\| i == 15) {`
207			`printf(" ");`
208			`}`
209			`printf("%c", psw & (1 << i) ? '1' : '0');`
210			`}`
211			`printf("\n");`
212			`}`
213
214
215			`static void doHelp(char *tokens[], int n) {`
216			`int i;`
217
218			`if (n == 1) {`
219			`help();`
220			`} else if (n == 2) {`
221			`for (i = 0; i < numCommands; i++) {`
222			`if (strcmp(commands[i].name, tokens[1]) == 0) {`
223			`(*commands[i].hlpProc)();`
224			`return;`
225			`}`
226			`}`
227			`printf("no help available for '%s', sorry\n", tokens[1]);`
228			`} else {`
229			`help00();`
230			`}`
231			`}`
232
233
234			`static void doArith(char *tokens[], int n) {`
235			`Word num1, num2, num3, num4;`
236
237			`if (n == 3) {`
238			`if (!getHexNumber(tokens[1], &num1)) {`
239			`printf("illegal first number\n");`
240			`return;`
241			`}`
242			`if (!getHexNumber(tokens[2], &num2)) {`
243			`printf("illegal second number\n");`
244			`return;`
245			`}`
246			`num3 = num1 + num2;`
247			`num4 = num1 - num2;`
248			`printf("add = %08X, sub = %08X\n", num3, num4);`
249			`} else {`
250			`help01();`
251			`}`
252			`}`
253
254
255			`static void doAssemble(char *tokens[], int n) {`
256			`Word addr;`
257			`Word psw;`
258			`char prompt[30];`
259			`char *line;`
260			`char *msg;`
261			`Word instr;`
262
263			`if (n == 1) {`
264			`addr = cpuGetPC();`
265			`} else if (n == 2) {`
266			`if (!getHexNumber(tokens[1], &addr)) {`
267			`printf("illegal address\n");`
268			`return;`
269			`}`
270			`} else {`
271			`help02();`
272			`return;`
273			`}`
274			`addr &= ~0x00000003;`
275			`psw = cpuGetPSW();`
276			`while (1) {`
277			`sprintf(prompt, "ASM @ %08X: ", addr);`
278			`line = getLine(prompt);`
279			`if (line == '\0' \|\| line == '\n') {`
280			`break;`
281			`}`
282			`addHist(line);`
283			`msg = asmInstr(line, addr, &instr);`
284			`if (msg != NULL) {`
285			`printf("%s\n", msg);`
286			`} else {`
287			`mmuWriteWord(addr, instr);`
288			`addr += 4;`
289			`}`
290			`}`
291			`}`
292
293
294			`static void doUnassemble(char *tokens[], int n) {`
295			`Word addr, count;`
296			`Word psw;`
297			`int i;`
298			`Word instr;`
299
300			`if (n == 1) {`
301			`addr = cpuGetPC();`
302			`count = 16;`
303			`} else if (n == 2) {`
304			`if (!getHexNumber(tokens[1], &addr)) {`
305			`printf("illegal address\n");`
306			`return;`
307			`}`
308			`count = 16;`
309			`} else if (n == 3) {`
310			`if (!getHexNumber(tokens[1], &addr)) {`
311			`printf("illegal address\n");`
312			`return;`
313			`}`
314			`if (!getHexNumber(tokens[2], &count)) {`
315			`printf("illegal count\n");`
316			`return;`
317			`}`
318			`if (count == 0) {`
319			`return;`
320			`}`
321			`} else {`
322			`help03();`
323			`return;`
324			`}`
325			`addr &= ~0x00000003;`
326			`psw = cpuGetPSW();`
327			`for (i = 0; i < count; i++) {`
328			`instr = mmuReadWord(addr);`
329			`printf("%08X: %08X %s\n",`
330			`addr, instr, disasm(instr, addr));`
331			`if (addr + 4 < addr) {`
332			`/* wrap-around */`
333			`break;`
334			`}`
335			`addr += 4;`
336			`}`
337			`}`
338
339
340			`static void doBreak(char *tokens[], int n) {`
341			`Word addr;`
342
343			`if (n == 1) {`
344			`cpuResetBreak();`
345			`showBreak();`
346			`} else if (n == 2) {`
347			`if (!getHexNumber(tokens[1], &addr)) {`
348			`printf("illegal address\n");`
349			`return;`
350			`}`
351			`addr &= ~0x00000003;`
352			`cpuSetBreak(addr);`
353			`showBreak();`
354			`} else {`
355			`help04();`
356			`}`
357			`}`
358
359
360			`static void doContinue(char *tokens[], int n) {`
361			`Word count, i;`
362			`Word addr;`
363
364			`if (n == 1) {`
365			`count = 1;`
366			`} else if (n == 2) {`
367			`if (!getHexNumber(tokens[1], &count) \|\| count == 0) {`
368			`printf("illegal count\n");`
369			`return;`
370			`}`
371			`} else {`
372			`help05();`
373			`return;`
374			`}`
375			`for (i = 0; i < count; i++) {`
376			`cpuRun();`
377			`}`
378			`addr = cpuGetPC();`
379			`printf("Break at %08X\n", addr);`
380			`showPC();`
381			`}`
382
383
384			`static void doStep(char *tokens[], int n) {`
385			`Word count, i;`
386
387			`if (n == 1) {`
388			`count = 1;`
389			`} else if (n == 2) {`
390			`if (!getHexNumber(tokens[1], &count) \|\| count == 0) {`
391			`printf("illegal count\n");`
392			`return;`
393			`}`
394			`} else {`
395			`help06();`
396			`return;`
397			`}`
398			`for (i = 0; i < count; i++) {`
399			`cpuStep();`
400			`}`
401			`showPC();`
402			`}`
403
404
405			`static void doPC(char *tokens[], int n) {`
406			`Word addr;`
407
408			`if (n == 1) {`
409			`showPC();`
410			`} else if (n == 2) {`
411			`if (!getHexNumber(tokens[1], &addr)) {`
412			`printf("illegal address\n");`
413			`return;`
414			`}`
415			`addr &= ~0x00000003;`
416			`cpuSetPC(addr);`
417			`showPC();`
418			`} else {`
419			`help07();`
420			`}`
421			`}`
422
423
424			`static void explainPSW(Word data) {`
425			`int i;`
426
427			`printf("interrupt vector : %s (%s)\n",`
428			`data & PSW_V ? "on " : "off",`
429			`data & PSW_V ? "RAM" : "ROM");`
430			`printf("current user mode : %s (%s)\n",`
431			`data & PSW_UM ? "on " : "off",`
432			`data & PSW_UM ? "user" : "kernel");`
433			`printf("previous user mode : %s (%s)\n",`
434			`data & PSW_PUM ? "on " : "off",`
435			`data & PSW_PUM ? "user" : "kernel");`
436			`printf("old user mode : %s (%s)\n",`
437			`data & PSW_OUM ? "on " : "off",`
438			`data & PSW_OUM ? "user" : "kernel");`
439			`printf("current interrupt enable : %s (%s)\n",`
440			`data & PSW_IE ? "on " : "off",`
441			`data & PSW_IE ? "enabled" : "disabled");`
442			`printf("previous interrupt enable : %s (%s)\n",`
443			`data & PSW_PIE ? "on " : "off",`
444			`data & PSW_PIE ? "enabled" : "disabled");`
445			`printf("old interrupt enable : %s (%s)\n",`
446			`data & PSW_OIE ? "on " : "off",`
447			`data & PSW_OIE ? "enabled" : "disabled");`
448			`printf("last interrupt acknowledged : %02X (%s)\n",`
449			`(data & PSW_PRIO_MASK) >> 16,`
450			`exceptionToString((data & PSW_PRIO_MASK) >> 16));`
451			`for (i = 15; i >= 0; i--) {`
452			`printf("%-35s: %s (%s)\n",`
453			`exceptionToString(i),`
454			`data & (1 << i) ? "on " : "off",`
455			`data & (1 << i) ? "enabled" : "disabled");`
456			`}`
457			`}`
458
459
460			`static void doPSW(char *tokens[], int n) {`
461			`Word data;`
462
463			`if (n == 1) {`
464			`data = cpuGetPSW();`
465			`showPSW();`
466			`explainPSW(data);`
467			`} else if (n == 2) {`
468			`if (!getHexNumber(tokens[1], &data)) {`
469			`printf("illegal data\n");`
470			`return;`
471			`}`
472			`data &= 0x0FFFFFFF;`
473			`cpuSetPSW(data);`
474			`showPSW();`
475			`explainPSW(data);`
476			`} else {`
477			`help08();`
478			`}`
479			`}`
480
481
482			`static void doRegister(char *tokens[], int n) {`
483			`int i, j;`
484			`int reg;`
485			`Word data;`
486
487			`if (n == 1) {`
488			`for (i = 0; i < 8; i++) {`
489			`for (j = 0; j < 4; j++) {`
490			`reg = 8 * j + i;`
491			`data = cpuGetReg(reg);`
492			`printf("$%-2d %08X ", reg, data);`
493			`}`
494			`printf("\n");`
495			`}`
496			`showPSW();`
497			`showBreak();`
498			`showPC();`
499			`} else if (n == 2) {`
500			`if (!getDecNumber(tokens[1], &reg) \|\| reg < 0 \|\| reg >= 32) {`
501			`printf("illegal register number\n");`
502			`return;`
503			`}`
504			`data = cpuGetReg(reg);`
505			`printf("$%-2d %08X\n", reg, data);`
506			`} else if (n == 3) {`
507			`if (!getDecNumber(tokens[1], &reg) \|\| reg < 0 \|\| reg >= 32) {`
508			`printf("illegal register number\n");`
509			`return;`
510			`}`
511			`if (!getHexNumber(tokens[2], &data)) {`
512			`printf("illegal data\n");`
513			`return;`
514			`}`
515			`cpuSetReg(reg, data);`
516			`} else {`
517			`help09();`
518			`}`
519			`}`
520
521
522			`static void doDump(char *tokens[], int n) {`
523			`Word addr, count;`
524			`Word psw;`
525			`Word lo, hi, curr;`
526			`int lines, i, j;`
527			`Word tmp;`
528			`Byte c;`
529
530			`if (n == 1) {`
531			`addr = cpuGetPC();`
532			`count = 16 * 16;`
533			`} else if (n == 2) {`
534			`if (!getHexNumber(tokens[1], &addr)) {`
535			`printf("illegal address\n");`
536			`return;`
537			`}`
538			`count = 16 * 16;`
539			`} else if (n == 3) {`
540			`if (!getHexNumber(tokens[1], &addr)) {`
541			`printf("illegal address\n");`
542			`return;`
543			`}`
544			`if (!getHexNumber(tokens[2], &count)) {`
545			`printf("illegal count\n");`
546			`return;`
547			`}`
548			`if (count == 0) {`
549			`return;`
550			`}`
551			`} else {`
552			`help10();`
553			`return;`
554			`}`
555			`psw = cpuGetPSW();`
556			`lo = addr & ~0x0000000F;`
557			`hi = addr + count - 1;`
558			`if (hi < lo) {`
559			`/* wrap-around */`
560			`hi = 0xFFFFFFFF;`
561			`}`
562			`lines = (hi - lo + 16) >> 4;`
563			`curr = lo;`
564			`for (i = 0; i < lines; i++) {`
565			`printf("%08X: ", curr);`
566			`for (j = 0; j < 16; j++) {`
567			`tmp = curr + j;`
568			`if (tmp < addr \|\| tmp > hi) {`
569			`printf(" ");`
570			`} else {`
571			`c = mmuReadByte(tmp);`
572			`printf("%02X", c);`
573			`}`
574			`printf(" ");`
575			`}`
576			`printf(" ");`
577			`for (j = 0; j < 16; j++) {`
578			`tmp = curr + j;`
579			`if (tmp < addr \|\| tmp > hi) {`
580			`printf(" ");`
581			`} else {`
582			`c = mmuReadByte(tmp);`
583			`if (c >= 32 && c <= 126) {`
584			`printf("%c", c);`
585			`} else {`
586			`printf(".");`
587			`}`
588			`}`
589			`}`
590			`printf("\n");`
591			`curr += 16;`
592			`}`
593			`}`
594
595
596			`static void doMemoryWord(char *tokens[], int n) {`
597			`Word psw;`
598			`Word addr;`
599			`Word data;`
600			`Word tmpData;`
601
602			`psw = cpuGetPSW();`
603			`if (n == 1) {`
604			`addr = cpuGetPC();`
605			`data = mmuReadWord(addr);`
606			`printf("%08X: %08X\n", addr, data);`
607			`} else if (n == 2) {`
608			`if (!getHexNumber(tokens[1], &addr)) {`
609			`printf("illegal address\n");`
610			`return;`
611			`}`
612			`data = mmuReadWord(addr);`
613			`printf("%08X: %08X\n", addr, data);`
614			`} else if (n == 3) {`
615			`if (!getHexNumber(tokens[1], &addr)) {`
616			`printf("illegal address\n");`
617			`return;`
618			`}`
619			`if (!getHexNumber(tokens[2], &tmpData)) {`
620			`printf("illegal data\n");`
621			`return;`
622			`}`
623			`data = tmpData;`
624			`mmuWriteWord(addr, data);`
625			`} else {`
626			`help11();`
627			`}`
628			`}`
629
630
631			`static void doMemoryHalf(char *tokens[], int n) {`
632			`Word psw;`
633			`Word addr;`
634			`Half data;`
635			`Word tmpData;`
636
637			`psw = cpuGetPSW();`
638			`if (n == 1) {`
639			`addr = cpuGetPC();`
640			`data = mmuReadHalf(addr);`
641			`printf("%08X: %04X\n", addr, data);`
642			`} else if (n == 2) {`
643			`if (!getHexNumber(tokens[1], &addr)) {`
644			`printf("illegal address\n");`
645			`return;`
646			`}`
647			`data = mmuReadHalf(addr);`
648			`printf("%08X: %04X\n", addr, data);`
649			`} else if (n == 3) {`
650			`if (!getHexNumber(tokens[1], &addr)) {`
651			`printf("illegal address\n");`
652			`return;`
653			`}`
654			`if (!getHexNumber(tokens[2], &tmpData)) {`
655			`printf("illegal data\n");`
656			`return;`
657			`}`
658			`data = (Half) tmpData;`
659			`mmuWriteHalf(addr, data);`
660			`} else {`
661			`help12();`
662			`}`
663			`}`
664
665
666			`static void doMemoryByte(char *tokens[], int n) {`
667			`Word psw;`
668			`Word addr;`
669			`Byte data;`
670			`Word tmpData;`
671
672			`psw = cpuGetPSW();`
673			`if (n == 1) {`
674			`addr = cpuGetPC();`
675			`data = mmuReadByte(addr);`
676			`printf("%08X: %02X\n", addr, data);`
677			`} else if (n == 2) {`
678			`if (!getHexNumber(tokens[1], &addr)) {`
679			`printf("illegal address\n");`
680			`return;`
681			`}`
682			`data = mmuReadByte(addr);`
683			`printf("%08X: %02X\n", addr, data);`
684			`} else if (n == 3) {`
685			`if (!getHexNumber(tokens[1], &addr)) {`
686			`printf("illegal address\n");`
687			`return;`
688			`}`
689			`if (!getHexNumber(tokens[2], &tmpData)) {`
690			`printf("illegal data\n");`
691			`return;`
692			`}`
693			`data = (Byte) tmpData;`
694			`mmuWriteByte(addr, data);`
695			`} else {`
696			`help13();`
697			`}`
698			`}`
699
700
701			`static void doTLB(char *tokens[], int n) {`
702			`int index;`
703			`TLB_Entry tlbEntry;`
704			`Word data;`
705
706			`if (n == 1) {`
707			`for (index = 0; index < TLB_SIZE; index++) {`
708			`tlbEntry = mmuGetTLB(index);`
709			`printf("TLB[%02d] page %08X frame %08X %c %c\n",`
710			`index, tlbEntry.page, tlbEntry.frame,`
711			`tlbEntry.write ? 'w' : '-',`
712			`tlbEntry.valid ? 'v' : '-');`
713			`}`
714			`printf("Index(1) %08X\n", mmuGetIndex());`
715			`printf("EntryHi(2) %08X\n", mmuGetEntryHi());`
716			`printf("EntryLo(3) %08X\n", mmuGetEntryLo());`
717			`} else if (n == 2) {`
718			`if (!getDecNumber(tokens[1], &index) \|\| index < 0 \|\| index >= TLB_SIZE) {`
719			`printf("illegal TLB index\n");`
720			`return;`
721			`}`
722			`tlbEntry = mmuGetTLB(index);`
723			`printf("TLB[%02d] page %08X frame %08X %c %c\n",`
724			`index, tlbEntry.page, tlbEntry.frame,`
725			`tlbEntry.write ? 'w' : '-',`
726			`tlbEntry.valid ? 'v' : '-');`
727			`} else if (n == 3) {`
728			`help14();`
729			`} else if (n == 4) {`
730			`if (!getDecNumber(tokens[1], &index) \|\| index < 0 \|\| index >= TLB_SIZE) {`
731			`printf("illegal TLB index\n");`
732			`return;`
733			`}`
734			`if (!getHexNumber(tokens[3], &data)) {`
735			`printf("illegal data\n");`
736			`return;`
737			`}`
738			`tlbEntry = mmuGetTLB(index);`
739			`if (strcmp(tokens[2], "p") == 0) {`
740			`tlbEntry.page = data & PAGE_MASK;`
741			`} else`
742			`if (strcmp(tokens[2], "f") == 0) {`
743			`tlbEntry.frame = data & PAGE_MASK;`
744			`tlbEntry.write = data & TLB_WRITE ? true : false;`
745			`tlbEntry.valid = data & TLB_VALID ? true : false;`
746			`} else {`
747			`printf("TLB selector is not one of 'p' or 'f'\n");`
748			`return;`
749			`}`
750			`mmuSetTLB(index, tlbEntry);`
751			`printf("TLB[%02d] page %08X frame %08X %c %c\n",`
752			`index, tlbEntry.page, tlbEntry.frame,`
753			`tlbEntry.write ? 'w' : '-',`
754			`tlbEntry.valid ? 'v' : '-');`
755			`} else {`
756			`help14();`
757			`}`
758			`}`
759
760
761			`static void doBoot(char *tokens[], int n) {`
762			`int dskno;`
763
764			`if (n == 2) {`
765			`if (!getDecNumber(tokens[1], &dskno) \|\| dskno < 0 \|\| dskno > 1) {`
766			`printf("illegal disk number\n");`
767			`return;`
768			`}`
769			`boot(dskno);`
770			`} else {`
771			`help15();`
772			`}`
773			`}`
774
775
776			`Command commands[] = {`
777			`{ "help", help00, doHelp },`
778			`{ "+", help01, doArith },`
779			`{ "a", help02, doAssemble },`
780			`{ "u", help03, doUnassemble },`
781			`{ "b", help04, doBreak },`
782			`{ "c", help05, doContinue },`
783			`{ "s", help06, doStep },`
784			`{ "@", help07, doPC },`
785			`{ "p", help08, doPSW },`
786			`{ "r", help09, doRegister },`
787			`{ "d", help10, doDump },`
788			`{ "mw", help11, doMemoryWord },`
789			`{ "mh", help12, doMemoryHalf },`
790			`{ "mb", help13, doMemoryByte },`
791			`{ "t", help14, doTLB },`
792			`{ "boot", help15, doBoot },`
793			`};`
794
795			`int numCommands = sizeof(commands) / sizeof(commands[0]);`
796
797
798			`static void doCommand(char *line) {`
799			`char *tokens[MAX_TOKENS];`
800			`int n;`
801			`char *p;`
802			`int i;`
803
804			`n = 0;`
805			`p = strtok(line, " \t\n");`
806			`while (p != NULL) {`
807			`if (n == MAX_TOKENS) {`
808			`printf("too many tokens on line\n");`
809			`return;`
810			`}`
811			`tokens[n++] = p;`
812			`p = strtok(NULL, " \t\n");`
813			`}`
814			`if (n == 0) {`
815			`return;`
816			`}`
817			`for (i = 0; i < numCommands; i++) {`
818			`if (strcmp(commands[i].name, tokens[0]) == 0) {`
819			`(*commands[i].cmdProc)(tokens, n);`
820			`return;`
821			`}`
822			`}`
823			`help();`
824			`}`
825
826
827			`static char *article(char firstLetterOfNoun) {`
828			`switch (firstLetterOfNoun) {`
829			`case 'a':`
830			`case 'e':`
831			`case 'i':`
832			`case 'o':`
833			`case 'u':`
834			`return "An";`
835			`default:`
836			`return "A";`
837			`}`
838			`}`
839
840
841			`static void interactiveException(int exception) {`
842			`char *what;`
843
844			`what = exceptionToString(exception);`
845			`printf("\n");`
846			`printf("NOTE: %s %s occurred while executing the command.\n",`
847			`article(*what), what);`
848			`printf(" This event will not alter the state of the CPU.\n");`
849			`}`
850
851
852			`void execCommand(char *line) {`
853			`MonitorState commandState;`
854
855			`if (saveState(&commandState)) {`
856			`/* initialization */`
857			`monitorReturn = &commandState;`
858			`doCommand(line);`
859			`} else {`
860			`/* an exception was thrown */`
861			`interactiveException((userContext.psw & PSW_PRIO_MASK) >> 16);`
862			`}`
863			`monitorReturn = NULL;`
864			`}`