Jordan Earls / MbedConsole Featured

A project to implement a console using the Mbed using VGA for video output and a PS/2 keyboard for the input. The eventual goal is to also include tools for managing SD cards, and a semi-self-hosting programming environment.

Dependencies:   PS2_MbedConsole fastlib SDFileSystem vga640x480g_mbedconsole lightvm mbed

MbedConsole is a cool little project to have a self-contained computer all on an Mbed. So far it has VGA and PS/2 support and can stand alone without a computer powering it. Next planned features are SD card support and a lightweight programmable VM complete with a file editor and self-hosted assembler.

You can view additional details about it at http://earlz.net/tags/mbedconsole

Diff: plEarlz.cpp

Revision:
5:367397a82ddc
Parent:
4:b44c27404035
Child:
6:a4dff59ef214
--- a/plEarlz.cpp	Wed Sep 19 05:05:31 2012 +0000
+++ b/plEarlz.cpp	Thu Sep 20 04:43:50 2012 +0000
@@ -28,6 +28,7 @@
 #define MAXSTACK 64
 #define MAXCALLS 32
 #define MAXLINELENGTH 128
+#define DICTIONARYSTEP 4 //how much memory to reserve when doing a reallocation for resizing
 
 int pl_stackpos=0;
 int pl_stack[MAXSTACK];
@@ -49,6 +50,27 @@
     Word,
     Quote
 };
+typedef void (*BuiltinFunction)(void);
+typedef struct
+{
+    char name[12];
+    enum Type{
+        Constant,
+        ConstantString,
+        Builtin,
+        Function
+    } type;
+    union valueunion{
+        int intvalue;
+        BuiltinFunction builtin;
+        char *string;
+    } value;
+} WordKey;
+
+
+int pl_dictionary_count=0;
+int pl_dictionary_size=0;
+WordKey *pl_dictionary; //todo: a hash table would be much faster
 
 void pl_push(int val)
 {
@@ -73,24 +95,89 @@
     return pl_stack[pl_stackpos];
 }
 
+WordKey *pl_lookup(char* name)
+{
+    for(int i=0;i<pl_dictionary_count;i++)
+    {
+        if(strlcmp(name, pl_dictionary[i].name, 12)==0)
+        {
+            return &pl_dictionary[i];
+        }
+    }
+    return NULL;
+}
+
+int pl_addword()
+{
+    if(pl_dictionary_size==0){
+        pl_dictionary=(WordKey*)malloc(sizeof(WordKey)*12);
+        pl_dictionary_size=12;
+        return 0;
+    }
+    if(pl_dictionary_size<=pl_dictionary_count)
+    {
+        void* tmp=realloc(pl_dictionary, pl_dictionary_size+sizeof(WordKey)*DICTIONARYSTEP);
+        if(tmp==NULL)
+        {
+            vputs("Out of memory!! Epic Fail!!");
+            return -1;
+        }
+        pl_dictionary=(WordKey*)tmp;
+        pl_dictionary_size+=sizeof(WordKey)*DICTIONARYSTEP;
+    }
+    return pl_dictionary_count++;
+}
+
 void execute_word(char *word, WordType type)
 {
     if(type==Number){
         pl_push(atoi(word));
     }else{
-        if(word[1]==0 && word[0]=='.')
+        if(word[1]==0) //check the quick builtins first
         {
-            int tmp=pl_pop();
-            sprintf( word, "%i\n", tmp);
-            vputs(word);
+            if(word[0]=='.'){
+                int tmp=pl_pop();
+                sprintf( word, "%i\n", tmp);
+                vputs(word);
+                return;
+            }else if(word[0]==';')
+            {
+                //...?
+            }else if(word[0]=='+'){
+                pl_push(pl_pop()+pl_pop());
+            }else if(word[0]=='/'){
+                pl_push(pl_pop()/pl_pop());
+            }else if(word[0]=='-'){
+                pl_push(pl_pop()-pl_pop());
+            }else if(word[0]=='!'){
+                pl_push(pl_pop()-pl_pop());
+            }else if(word[0]=='%'){
+                pl_push(pl_pop()%pl_pop());
+            }else if(word[0]=='*'){
+                pl_push(pl_pop()*pl_pop());
+            }else if(word[0]=='!'){
+                int tmp=pl_pop();
+                int* tmp2=(int*)pl_pop();
+                *tmp2=tmp;
+            }else if(word[0]=='?'){
+                pl_push(*(int*)pl_pop());
+            }else if(word[0]=='='){
+                pl_push(pl_pop() == pl_pop());
+            }else if(word[0]=='`'){
+                pl_push(pl_pop()>0);
+            }else if(word[0]=='$'){
+                //print string (address on stack
+            }
+        
         }else{
             vputs("I don't know the word ");
             vputs(word);
             vputs("\n");
         }
     }
+}
 
-}
+
 
 void parse_line(char *line)
 {
@@ -102,7 +189,7 @@
     for(int i=0;i<len;i++)
     {
         char c=line[i];
-        if(is_whitespace(c))
+        if(is_whitespace(c) || c=='\\')
         {
             if(word[0]!=0)
             {
@@ -112,6 +199,9 @@
             }
             wordpos=0;
             type=Unknown;
+            if(c=='\\'){
+                return; //rest is a comment
+            }
         }else if(is_numeric(c)){
             if(type==Unknown){
                 type=Number;