void PARSER_ParseUart(char *str)
{
    str = ToLower(str);
    if(strlen(str) == 0)
        goto exit;
    char *command;
    char *argument1="";
    char *argument2="";
    char *argument3="";
    command = strtok(str," ");
    argument1 = strtok (NULL, " ");
    argument2 = strtok (NULL, " ");
    argument3 = strtok (NULL, " ");
    if(strcmp(command,"command1")==0)
    {
        if(argument1 == NULL)
        {
                  UART_SendInt(UART0,FunctionReadsValue());    
          }
        else
        {
            int val1 = atoi(argument1);
            FunctionWritesValue(val1);
        }
    }
    else if(strcmp(command,"command2")==0)
    {
        if(argument1 == NULL)
        {
                UART_SendInt(UART0,FunctionReadsValue());
        }
        else if (argument2 == NULL || argument3 == NULL)
        {
           FunctionDoSmething();
        }
             else
             {
                FunctionDoAnotherThing();
             }
       }
       //and so on………………        
}

struct command
{
    char *name;  //command name
    char mode;   //0-read, 1- read/write
    int minval;  
    int maxval;
    char val_changed;  
    void (*fp) (void);  //function pointer
};

struct command commands[10];

struct command commands[] = {
    {"imax", 1, 1000, 10000, 0, get_imax},
    {"inow", 0, 1000, 10000, 0, get_inow},
    {"top",  1, 100,  2500,  0, get_top},
    {"pos",  0, 100000, 100000, 0, get_pos},
};

void get_command(char *com)
{
     int I;
     for (i = 0; i < sizeof(commands); i++)
     {
         if(strcmp(commands[i].name, com) == 0)
         {
            //do something
         }
     }
}