Created a basic binary format to help guide the disassembler.

misc/test.asm

@@ -1,7 +1,7 @@
 ;.org 0x100
-;.db msg "Hello, world!", 0
+.db msg "Hello, world!", 0
 ;.db more_stuff "AA", 0
-copy r7, 45 ; //
+copy r7, msg ; //
 cmp r8, 45 ;1000 1111
 add r4, 30
 sub r1, 69
@@ -17,4 +17,6 @@ jz 45
 ;mov r1, 5   ; move the immediate value 5 into r1
 ;add r1,5   ; add 5 into r1
 ;int 21      ; maybe that will call some string drawing BIOS-like routine
-;ret
+;ret
+; 4 byte header
+; | Address of First Opcode (2 bytes) | End of Binary (2 bytes) |

src/disass.c

@@ -17,14 +17,17 @@ void GetParameter(unsigned char instruction, char* text);
 
 void Disassemble(unsigned char image[HIGHMEMORY]) {
     Image = image;
-    int position = 0;
+    int position = image[0] + image[1];
+    int end = image[2] + image[3];
+
+    printf("Start: %d and End: %d\n", position, end);
 
     char* parameter1 = calloc(32, sizeof(char));
     char* parameter2 = calloc(32, sizeof(char));
 
     unsigned char instruction = image[position];
 
-    while(instruction != 0) {
+    while(end >= position) {//(instruction != 0) {
         // printf("%d\n", position);
         // printf("%#04X\n", instruction);
         
@@ -119,7 +122,7 @@ int IsRegisterPattern(unsigned char pattern, char* lexeme) {
     return 1;
 }
 /*
-//REG       XXX0 0XXX 1010 1111
+//REG       XXX0 0XXX
 //Constant  XXX0 1XXX
 //Address   XXX1 0XXX
     NOP  - 0000 0000 NOP

src/parser.c

@@ -18,6 +18,8 @@ struct intr {
 Symbol* CreateSymbol(Token* token, int address);
 const List* TokensList;
 int CurrentToken = 0;
+//int HeapStart = 4; // zero indexed, used for declared variables.
+//int BinaryEnd = 4; // Zero indexed (binary starts with a 4 byte header)
 
 void AddSymbol(Token*, int);
 void PrintSymbols(void);
@@ -30,13 +32,18 @@ int Expect(int, ...);
 int ExpectTokenClass(int, ...);
 const Symbol* GetSymbol(char*);
 List* SymbolsTable;
+void WriteMemory(unsigned char value, int location);
+void WriteMemoryORMask(unsigned char mask, int location);
+unsigned int HeapTop = 4;
 unsigned int ProgramCounter = 0;
+unsigned char Heap[HIGHMEMORY];
 unsigned char Memory[HIGHMEMORY];
 
 unsigned char* ParseTokens(List* tokens) {
     if (!tokens) return NULL;
 
     memset(Memory, 0, sizeof(Memory));
+    memset(Heap, 0, sizeof(Heap));
 
     TokensList = tokens;
 
@@ -68,14 +75,23 @@ unsigned char* ParseTokens(List* tokens) {
     if (SymbolsTable->size > 0) PrintSymbols();
 
     DestroyList(SymbolsTable);
+
+    memcpy(&Heap[HeapTop], Memory, ProgramCounter);
+    int totalSize = HeapTop + ProgramCounter;
+    Heap[0] = 2 >> HeapTop & 0xFF;
+    Heap[1] = HeapTop & 0xFF;
+    Heap[2] = 2 >> totalSize & 0xFF;
+    Heap[3] = totalSize & 0xFF;
+
     for(int i = 0; i < 33; i++) { 
         if (i != 0 && i % 3 == 0) printf("\n");
-        printf("%02X ", Memory[i] & 0xFF);
+        printf("%02X ", Heap[i] & 0xFF);
     }
     printf("\n");
-    // printf("Program Counter: %d\n", ProgramCounter);
+    printf("Program Counter: %d\n", ProgramCounter);
-    //printf("Heap Top: %#06X\n", HeapTop);
+    printf("Heap Top: %#06X\n", HeapTop);
-    return Memory;
+
+    return Heap;
 }
 
 void HandleAssemblerDirective(void) {
@@ -86,21 +102,25 @@ void HandleAssemblerDirective(void) {
         Token* identifier = PeekToken();
 
         if (!Expect(1, IDENTIFIER)) {
-            fprintf(stderr, "Expected identifier on line %d\n", PeekToken()->line);
+            fprintf(stderr, "Expected identifier on line %d\n", identifier->line);
             exit(1);
         }
 
         AddSymbol(identifier, ProgramCounter);
 
-        switch(PeekToken()->type) {
+        identifier = PeekToken();
-            case STRING:
-                printf("[INFO] %s = '%s' (%#04X)\n", identifier->lexeme, PeekToken()->lexeme, ProgramCounter);
 
-                for(int i = 0; i < strlen(PeekToken()->lexeme); i++) {
+        switch(identifier->type) {
-                    Memory[ProgramCounter + i] = PeekToken()->lexeme[i];
+            case STRING:
+                printf("[INFO] %s = '%s' (%#04X)\n", identifier->lexeme, identifier->lexeme, ProgramCounter);
+
+                for(int i = 0; i < strlen(identifier->lexeme); i++) {
+                    //Memory[ProgramCounter + i] = PeekToken()->lexeme[i];
+                    Heap[HeapTop + i] = identifier->lexeme[i];
                 }
 
-                ProgramCounter += strlen(PeekToken()->lexeme);
+                //ProgramCounter += strlen(PeekToken()->lexeme);
+                HeapTop += strlen(identifier->lexeme);
 
                 AdvanceParser();
 
@@ -113,8 +133,10 @@ void HandleAssemblerDirective(void) {
                     }
                     else {
                         //Add the NULL byte.
-                        Memory[ProgramCounter] = '\0';
+                        //Memory[ProgramCounter] = '\0';
-                        ProgramCounter++;
+                        Heap[HeapTop] = '\0';
+                        //ProgramCounter++;
+                        HeapTop++;
                         return;
                     }
                 }
@@ -153,7 +175,7 @@ void HandleRegisterBasedOpcode(unsigned char instruction, unsigned char mask) {
 
     token = PeekToken();
 
-    if (token->token_class == IDENTIFIER || token->token_class == LABEL) {
+    if (token->type == IDENTIFIER || token->type == LABEL) {
         const Symbol* symbol = GetSymbol(token->lexeme);
 
         if (!symbol) {
@@ -363,4 +385,22 @@ int ParserAtEnd(void) {
 
 Token* PeekToken(void) {
     return TokensList->content[CurrentToken];
+}
+
+void WriteMemory(unsigned char value, int location) {
+    if (location > HIGHMEMORY) {
+        fprintf(stderr, "[Error] Exceeded memmory size\n");
+        exit(1);
+    }
+
+    Memory[location] = value;
+}
+
+void WriteMemoryORMask(unsigned char mask, int location) {
+    if (location > HIGHMEMORY) {
+        fprintf(stderr, "[Error] Exceeded memmory size\n");
+        exit(1);
+    }
+
+    Memory[location] |= mask;
 }