A equ eax
B equ ebx
C equ ecx
X equ edx
Y equ ebp
Z equ esp
I equ esi
J equ edi

@A = 0
@B = 1
@C = 2
@X = 3
@Y = 4
@Z = 5
@I = 6
@J = 7

@SET = 0x1
@ADD = 0x2
@SUB = 0x3
@MUL = 0x4
@DIV = 0x5
@MOD = 0x6
@SHL = 0x7
@SHR = 0x8
@AND = 0x9
@BOR = 0xA
@XOR = 0xB
@IFE = 0xC
@IFN = 0xD
@IFG = 0xE
@IFB = 0xF

@JSR = 0x01

macro parse_operand value {
   define v value
   @nextword = -1
   match =POP,v \{
     define v
     @value = 0x18
   \}
   match =PEEK,v \{
     define v
     @value = 0x19
   \}
   match =PUSH,v \{
     define v
     @value = 0x1A
   \}
   match =SP,v \{
     define v
     @value = 0x1B
   \}
   match =PC,v \{
     define v
     @value = 0x1C
   \}
   match =O,v \{
     define v
     @value = 0x1D
   \}
   match [addr],v \{
     define v
     if +addr relativeto 0
       @value = 0x1E
       @nextword = word addr
     irps reg,A B C X Y Z I J \\{
       else if +addr relativeto reg
         if +addr-reg = 0
           @value = 0x08 + @\\#reg
         else
           @value = 0x10 + @\\#reg
           @nextword = +addr-reg
         end if
     \\}
     end if
   \}
   match expr,v \{
     define v
     if +expr relativeto 0
       if expr>=0 & expr<=0x1F
         @value = 0x20 + expr
       else
         @value = 0x1F
         @nextword = word expr
       end if
     irps reg,A B C X Y Z I J \\{
       else if +expr relativeto reg
         assert +expr-reg = 0
         @value = 0x00 + @\\#reg
     \\}
     end if
   \}
}

macro basic_instruction opcode,a,b {
  @word1 = opcode and 1111b
  parse_operand a
  @word1 = @word1 or @value shl 4
  @word2 = @nextword
  parse_operand b
  @word1 = @word1 or @value shl (4+6)
  @word3 = @nextword
  db @word1 shr 8,@word1 and 0FFh
  if @word2>=0
    db @word2 shr 8,@word2 and 0FFh
  end if
  if @word3>=0
    db @word3 shr 8,@word3 and 0FFh
  end if
}

macro nonbasic_instruction opcode,a {
  @word1 = (opcode and 111111b) shl 4
  parse_operand a
  @word1 = @word1 or @value shl (4+6)
  db @word1 shr 8,@word1 and 0FFh
  if @nextword>=0
    db @nextword shr 8,@nextword and 0FFh
  end if
}

irps instr,SET ADD SUB MUL DIV MOD SHL SHR AND BOR XOR IFE IFN IFG IFB {
  macro instr a,b \{ basic_instruction @\#instr,a,b \}
}

irps instr,JSR {
  macro instr a \{ nonbasic_instruction @\#instr,a \}
}

macro LABEL name {
  name = $ shr 1
}    

; Try some basic stuff
              SET A, 0x30
              SET [0x1000], 0x20
              SUB A, [0x1000]
              IFN A, 0x10
              SET PC, crash

; Do a loopy thing
              SET I, 10
              SET A, 0x2000
LABEL _loop
              SET [0x2000+I], [A]
              SUB I, 1
              IFN I, 0
              SET PC, _loop

; Call a subroutine
              SET X, 0x4
              JSR testsub
              SET PC, crash

LABEL testsub
              SHL X, 4
              SET PC, POP

; Hang forever. X should now be 0x40 if everything went right.
LABEL crash
              SET PC, crash    

000000  [ 2 ]  A = 0x30
000002  [ 3 ]  [0x1000] = 0x20
000005  [ 3 ]  A = A - [0x1000]
000007  [2+1]  IF ( A != 0x10 )
000008  [ 1 ]      GOTO 0x16
000009  [ 1 ]  I = 0xa
00000a  [ 2 ]  A = 0x2000
00000c  [ 2 ]  [I + 0x2000] = [A]
00000e  [ 2 ]  I = I - 0x1
00000f  [2+1]  IF ( I != 0 )
000010  [ 1 ]      goto 0xc
000011  [ 1 ]  X = 0x4
000012  [ 2 ]  CALL 0x14
000013  [ 1 ]  GOTO 0x16
000014  [ 2 ]  X = X << 0x4
000015  [ 1 ]  RET
000016  [ 1 ]  GOTO 0x16    

#define showHex 1
#define showLines 2
#define showCycles 4
#define showHR 8
#define noshowAsm 16
#define showInd 32
int cmdFlags;
    

    if (o->code.opcode == 0)
 {
              if(o->n.opcode == 1)
             {
                      ret = printf("%s\t", opcodeNames_nbasic[o->n.opcode]);
                        ret += valPrint(o->n.a_type, o->n.a);
         }
              else
                        ret = printf("%s\t", opcodeNames_nbasic[0]);
     }
    

          if (cmdFlags & showCycles)
              {
                      if(o->b.opcode == 0 && o->n.opcode != 1)
                              printf("[???]  ");
                        else if (o->b.opcode >= 0xC)
                          printf("[%i+1]  ", instrGetCycles(o));
                    else
                                printf("[ %i ]  ", instrGetCycles(o));
            }
    

void instrDisasm(const word inp[], int len)
{
      int cur = 0, delta;