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--- user:jr018429:portfolio:cpumemory [2011/05/18 23:20] – jr018429
+++ user:jr018429:portfolio:cpumemory [2011/05/18 23:48] (current) – jr018429
@@ Line 1: / Line 1: @@
+====== CPUMEM ======
+class library is included before the main function like this:\\
+<code>
+#include "cpumem.h"
+</code>
+\\
+CPUMEM::CPUMEM() is the constructor and automatically creates memory of the correct size, 64k (65536 elements, 0-65535), and type 1 byte (8-bits) for the 8085. The constructor is called automatically as the object is being instantiated.\\
+An object of the type CPUMEM is instatiated like this:\\
+\\
+<code>
+//Instantiates an object of type CPUMEM
+CPUMEM cpumemory;
+</code>
+\\
+CPUMEM::~CPUMEM() is the destructor and automatically deallocates the memory which was created when an object of type CPUMEM when an object of this type goes out of scope.\\
+\\
+unsigned char& CPUMEM::operator[](unsigned short int address) is a depricated member function. It uses overloaded operators to make the code that calls this method look like an array. **Do NOT use it.**\\
+\\
+unsigned char CPUMEM::read(unsigned short int address) is the member function that is used to read the 8-bit (unsigned char) value at a specific address.\\
+The **read** member function is used like this:\\
+<code>
+//reads 8-bit data from last memory address, 0xffff, or 65535
+unsigned char value = cpumemory.read(0xffff);
+</code>
+\\
+void CPUMEM::write(unsigned short int address, unsigned char value) is the member function that is used to write an 8-bit value to a specific address.\\
+The **write** member function is used like this:\\
+<code>
+//writes the value 0xff, or 255, to the last memory address 0xffff, or 65535
+cpumemory.write(0xffff, 0xff);
+</code>
+\\
+**cpumem.h**\\
+<code>
+#ifndef _CPUMEM_H
+#define _CPUMEM_H
+class CPUMEM
+{
+        public:
+                CPUMEM();
+                unsigned char& operator[](unsigned short int address);
+                unsigned char read(unsigned short int address);
+                void write(unsigned short int address, unsigned char value);
+                ~CPUMEM();
+        private:
+                //unsigned short int memlngth;
+                unsigned char *memadd;
+};
+#endif
+</code>
+\\
+**cpumem.cc**\\
+<code>
+#include "cpumem.h"
+CPUMEM::CPUMEM()
+{
+        memadd = new unsigned char[65536];
+}
+CPUMEM::~CPUMEM()
+{
+        delete[] memadd;
+}
+unsigned char& CPUMEM::operator[](unsigned short int address)
+{
+        return memadd[address];
+}
+unsigned char CPUMEM::read(unsigned short int address)
+{
+        return *(memadd + address);
+}
+void CPUMEM::write(unsigned short int address, unsigned char value)
+{
+        *(memadd + address) = value;
+}
+</code>
+\\
+**memtest.cc**\\
+<code>
+#include <cstdio>
+#include "cpumem.h"
+const int MEM_MAX = 65535;
+int main()
+{
+        CPUMEM datamemory;
+        for (int temp = 0x00; temp <= MEM_MAX; temp++) datamemory.write(temp, 255);
+        for(int temp = 0x00; temp <= MEM_MAX; temp++) printf("Memory address %x contains the value %x\n", temp, datamemory.read(temp));
+        return(0);
+}
+</code>
+\\
+**Makefile**\\
+<code>
+CXX = g++ $(CXXFLAGS) $(INC) $(LIBS)
+AR = ar
+CXXFLAGS = -Wall
+INC = -I ../../include/
+LIBS =
+SRC = cpumem.cc memtest.cc
+OBJ = $(SRC:.cc=.o)
+BIN = memtest
+all: $(SRC) $(BIN)
+debug: CXX += -DDEBUG -g
+debug: DEBUG = debug
+debug: $(SRC) $(BIN)
+$(BIN): $(OBJ)
+ifneq ($(MAKECMDGOALS),debug)
+        @printf "[CC]  %-20s ... " "$(BIN)"
+        @$(CXX) -o $(BIN) $(OBJ) && echo "SUCCESS" || echo "FAIL"
+else
+        $(CXX) -o $(BIN) $(OBJ)
+endif
+.cc.o:
+ifneq ($(MAKECMDGOALS),debug)
+        @printf "[B]   %-20s ... " "$<"
+        @$(CXX) -c $< && echo "OK" || echo "FAIL"
+else
+        $(CXX) -c $<
+endif
+clean:
+        rm -f *.o $(BIN) core
+default: $(BIN)
+</code>

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