initial commit

Makefile

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+LDFLAGS=-L/usr/local/lib
+CXXFLAGS=-Wall -I .. -I . -O3
+
+TSRC=cpu.cpp util/testharness.cpp
+
+all:
+	@echo There is no 'all' target. Yet.
+
+clean:
+	rm -f *.o *~ */*.o */*~ testharness.basic testharness.verbose testharness.extended
+
+test: $(TSRC)
+	g++ $(CXXFLAGS) -DBASICTEST $(TSRC) -o testharness.basic
+	g++ $(CXXFLAGS) -DVERBOSETEST $(TSRC) -o testharness.verbose
+	g++ $(CXXFLAGS) -DEXTENDEDTEST $(TSRC) -o testharness.extended
+

README.txt

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+Aiie!
+=====
+
+Aiie! is an Apple //e emulator, written ground-up for the Teensy
+3.6.
+
+The name comes from a game I used to play on the Apple //e back
+around 1986 - Ali Baba and the Forty Thieves, published by Quality
+Software in 1981.
+
+http://crpgaddict.blogspot.com/2013/07/game-103-ali-baba-and-forty-thieves-1981.html
+
+When characters in the game did damage to each other, they exclaimed
+something like "HAH! JUST A SCRATCH!" or "AAARGH!" or "OH MA, I THINK
+ITS MY TIME" [sic]. One of these exclamations was "AIIYEEEEE!!"
+
+Build log:
+----------
+
+  https://hackaday.io/project/19925-aiie-an-embedded-apple-e-emulator
+
+CPU
+===
+
+The CPU is a 65C02, not quite complete; it supports all of the 65C02
+documented opcodes but not the undocumented ones here:
+
+	   http://www.oxyron.de/html/opcodes02.html
+
+The timing of the CPU is also not quite correct. It's close, but
+doesn't count cycles due to page boundary crossings during branch
+instructions. (See the "cycle count footnotes" in cpu.cpp.)
+
+The CPU passes the 6502 functional test from here:
+
+    https://github.com/Klaus2m5/6502_65C02_functional_tests
+
+... which is included in binary form in the test harness (see the .h
+files in util/ for notes).
+
+testharness.basic should reach "test number 240", hang for a while,
+and then exit.
+
+testharness.verbose should show that it gets through 43 tests, test
+240, and then loops repeatedly for a while (exiting at a somewhat
+arbitrary point).
+
+testharness.extended currently fails (hanging at 0x733) because I
+haven't implemented the undocumented opcodes. It should get to address
+0x24a8 and hang. Some day I'll finish implementing all of the
+undocumented opcodes :)
+

cpu.h

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+#ifndef __CPU_H
+#define __CPU_H
+
+#include <stdlib.h>
+#include <stdint.h>
+
+class MMU;
+
+// Flags (P) register bit definitions.
+// Negative
+#define F_N (1<<7)
+// Overflow
+#define F_V (1<<6)
+#define F_UNK (1<<5) // What the heck is this?
+// Break
+#define F_B (1<<4)
+// Decimal
+#define F_D (1<<3)
+// Interrupt Disable
+#define F_I (1<<2)
+// Zero
+#define F_Z (1<<1)
+// Carry
+#define F_C (1<<0)
+
+class Cpu {
+ public:
+  Cpu();
+  ~Cpu();
+
+  void Reset();
+
+  void nmi();
+  void rst();
+  void brk();
+  void irq();
+
+  uint8_t Run(uint8_t numSteps);
+  uint8_t step();
+
+  uint8_t X();
+  uint8_t Y();
+  uint8_t A();
+  uint16_t PC();
+  uint8_t SP();
+  uint8_t P();
+
+ protected:
+  // Stack manipulation
+  void pushS8(uint8_t b);
+  void pushS16(uint16_t w);
+  uint8_t popS8();
+  uint16_t popS16();
+
+ public:
+  void SetMMU(MMU *mmu) { this->mmu = mmu; }
+
+ public:
+  uint16_t pc;
+  uint8_t sp;
+  uint8_t a;
+  uint8_t x;
+  uint8_t y;
+  uint8_t flags;
+
+  uint32_t cycles;
+  
+  MMU *mmu;
+};
+
+
+
+#endif

mmu.h

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+#ifndef __MMU_H
+#define __MMU_H
+
+#include <stdint.h>
+
+class MMU {
+ public:
+  virtual ~MMU() {}
+
+  virtual void Reset() = 0;
+
+  virtual uint8_t read(uint16_t mem) = 0;
+  virtual void write(uint16_t mem, uint8_t val) = 0;
+  virtual uint8_t readDirect(uint16_t address, uint8_t fromPage) = 0;
+};
+
+#endif

util/testharness.cpp

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+#include <stdio.h>
+#include <time.h>
+#include <string.h>
+
+#include "cpu.h"
+#include "mmu.h"
+
+#ifdef BASICTEST
+#include "6502_functional_test.h"
+#elif defined(VERBOSETEST)
+#include "6502_functional_test_2.h"
+#elif defined(EXTENDEDTEST)
+#include "65C02_extended_opcodes_test.h"
+#else
+#error undefined test - specify one of BASICTEST, VERBOSETEST, or EXTENDEDTEST
+#endif
+
+class TestMMU : public MMU {
+public:
+  TestMMU() {}
+  virtual ~TestMMU() {}
+
+  virtual void Reset() {}
+
+  virtual uint8_t read(uint16_t mem) { if (mem == 0xBFF0) { return 'R'; } return ram[mem];}
+  virtual void write(uint16_t mem, uint8_t val) {
+    if (mem == 0xBFF0) {printf("%c", val); return;} 
+    if (mem == 0x200) {printf("Start test %d\n", val);}
+    ram[mem] = val;}
+  virtual uint8_t readDirect(uint16_t address, uint8_t fromPage) { return read(address);}
+
+  uint8_t ram[65536];
+};
+
+Cpu cpu;
+TestMMU mmu;
+
+int main(int argc, char *argv[])
+{
+  cpu.SetMMU(&mmu);
+  cpu.rst();
+
+  // Load the 6502 functional test
+  memcpy(mmu.ram, functest, 0x10000);
+  cpu.pc = 0x400;
+  //  cpu.Reset();
+
+  time_t startTime = time(NULL);
+  // call cpu.Run() in the worst possible way (most overhead)
+  for (uint32_t i=0; i<1000000000; i++) {
+    cpu.Run(1);
+    
+#if 0
+    if (cpu.pc < 0x477F) {
+      printf("%llu OP $%.2X #%d 0x%.2X X 0x%.2X Y 0x%.2X A 0x%.2X SP 0x%.2X S 0x%.2X\n", cpu.cycles, mmu.read(cpu.pc), mmu.read(0x200), cpu.pc, cpu.x, cpu.y, cpu.a, cpu.sp, cpu.flags);
+    }
+#endif
+  }
+  time_t endTime = time(NULL);
+
+  printf("%ld seconds\n", endTime - startTime);
+  printf("Ending PC: 0x%X\n", cpu.pc);
+  
+}