diff --git a/acia.h b/acia.h
new file mode 100644
index 0000000..06a9540
--- /dev/null
+++ b/acia.h
@@ -0,0 +1,39 @@
+/*
+ * acia.h -- ACIA device
+ */
+struct acia {
+  
+  // status bits returned by operator byte
+  //
+  static const byte rdrf = 1 << 0;
+  static const byte tdre = 1 << 1;
+  static const byte dcd = 1 << 2;
+  static const byte cts = 1 << 3;
+  static const byte fe = 1 << 4;
+  static const byte ovrn = 1 << 5;
+  static const byte pc = 1 << 6;
+  static const byte irq = 1 << 7;
+
+  // control operations (four combinable groups)
+  //
+  static const byte cd1 = 0x00;		// divide by 1
+  static const byte cd16 = 0x01;		// divide by 16
+  static const byte cd64 = 0x02;		// divide by 64
+  static const byte reset = 0x03;	// master reset
+	
+  static const byte ws7e2 = 0 << 2;	// parity
+  static const byte ws7o2 = 1 << 2;
+  static const byte ws7e1 = 2 << 2;
+  static const byte ws7o1 = 3 << 2;
+  static const byte ws8n2 = 4 << 2;
+  static const byte ws8n1 = 5 << 2;
+  static const byte ws8e1 = 6 << 2;
+  static const byte ws8o1 = 7 << 2;
+
+  static const byte lrts_dti = 0 << 5;		// /rts, disable trans irq 
+  static const byte lrts_eti = 1 << 5;		// /rts, enable
+  static const byte hrts_dti = 2 << 5;		// rts, disable
+  static const byte lrts_dti_brk = 3 << 5;	// /rts, disable, send brk
+
+  static const byte eri = 1 << 7;	// enable receive interrupt
+};
diff --git a/cpu.h b/cpu.h
new file mode 100644
index 0000000..4d41e47
--- /dev/null
+++ b/cpu.h
@@ -0,0 +1,26 @@
+/*
+ * cpu.h
+ */
+#ifndef _CPU_H
+#define _CPU_H
+
+#ifndef _SETJMP_H
+#include <setjmp.h>
+#endif
+
+class CPU {
+public:
+	virtual void reset () =0;
+	virtual Memory::address run (unsigned instructions) =0;
+	virtual void raise (int level) =0;
+	virtual char *status () =0;
+
+	typedef void (*statfn) (const char *, ...);
+
+protected:
+	CPU (Memory *m, jmp_buf *e, statfn s): _memory(m), _err(e), _status(s){}
+	Memory *_memory;
+	jmp_buf *_err;
+	statfn _status;
+};
+#endif
diff --git a/hardware.h b/hardware.h
new file mode 100644
index 0000000..58e1060
--- /dev/null
+++ b/hardware.h
@@ -0,0 +1,34 @@
+/*
+ * The hardware configuration of the machine. 
+ * (This should be the same for all emulated devices.)
+ */
+#ifndef __HARDWARE_H
+#define __HARDWARE_H
+
+// TFT display...
+// NOTE: edit memorysaver.h to select the correct chip for your display!
+// Daniel Rebollo's boosterpack
+#define TFT_BACKLIGHT	PD_6
+#define TFT_MODEL	SSD1289
+// TFT01_2.4: http://www.elecfreaks.com/store/24-tft-lcd-tft0124-p-110.html
+// #undef TFT_BACKLIGHT
+// #define TFT_MODEL	S6D1121_8
+#define TFT_RS		PC_6
+#define TFT_WR		PC_5
+#define TFT_CS		PC_7
+#define TFT_RST		PC_4
+
+// SPI-RAM
+#define SPIRAM_CS       PE_0
+#define SPIRAM_SPI      1
+#define SPIRAM_DEV      SPI_for_SD
+
+// PS/2 keyboard
+#define KBD_DATA	PE_4
+#define KBD_IRQ		PE_5
+
+// "tape" storage...
+#define SD_CS		PF_3
+#define SD_SPI		1
+
+#endif
diff --git a/memory.cpp b/memory.cpp
new file mode 100644
index 0000000..f5395fc
--- /dev/null
+++ b/memory.cpp
@@ -0,0 +1,24 @@
+#include "memory.h"
+
+void Memory::put (Device &dev, address b) {
+  Device **d = _pages + b/page_size;
+
+  int size = dev.pages();
+  while (size--)
+    *d++ = &dev;
+
+  dev.base(b);
+}
+
+class NullDevice: public Memory::Device {
+  public:
+    NullDevice(): Memory::Device(65536) {}
+    void operator= (byte b) {}
+    operator byte() { return 0; }
+} nd;
+
+Memory::Memory() {
+  put(nd, 0);
+}
+  
+    
diff --git a/memory.h b/memory.h
new file mode 100644
index 0000000..9944fe8
--- /dev/null
+++ b/memory.h
@@ -0,0 +1,49 @@
+/*
+ * memory.h
+ */
+#ifndef _MEMORY_H
+#define _MEMORY_H
+
+typedef unsigned char byte;
+
+class Memory {
+public:
+	typedef unsigned short address;
+	static const int page_size = 256;
+
+	class Device {
+	public:
+		Device (int bytes): _pages(bytes/page_size) {}
+		virtual ~Device () {}
+		int pages () const { return _pages; }
+		void access (address a) { _acc=a-_base; }
+		void base (address a) { _base=a; }
+		address base () const { return _base; }
+
+		virtual void operator= (byte) =0;
+		virtual operator byte () =0;
+
+	protected:
+		address _acc, _base;
+	private:
+		int _pages;
+	};
+
+	// insert a new device instance
+	//
+	void put (Device &d, address at);
+	Device *get (address at) const { return _pages[at/page_size]; }
+
+	// primary access interface
+	//
+	Device &operator[] (address a) { 
+		Device *d = get (a);
+		d->access (a);
+		return *d;
+	}
+
+        Memory();
+private:
+	Device *_pages[256];
+};
+#endif
diff --git a/prom.h b/prom.h
new file mode 100644
index 0000000..c06048b
--- /dev/null
+++ b/prom.h
@@ -0,0 +1,10 @@
+class prom: public Memory::Device {
+public:
+	virtual void operator= (byte) {}
+	virtual operator byte () { return _mem[_acc]; }
+
+	prom(const byte *mem, int bytes): Memory::Device(bytes), _mem(mem) {}
+
+private:
+	const byte *_mem;
+};
diff --git a/ps2drv.cpp b/ps2drv.cpp
new file mode 100644
index 0000000..0efd5c9
--- /dev/null
+++ b/ps2drv.cpp
@@ -0,0 +1,81 @@
+#include <Energia.h>
+#include "ps2drv.h"
+
+#define BUFFER_SIZE 16
+static volatile uint8_t buffer[BUFFER_SIZE];
+static volatile uint8_t head, tail;
+static bool isbrk;
+static uint8_t DataPin;
+
+// The ISR for the external interrupt
+void ps2interrupt(void)
+{
+  static uint8_t bitcount=0;
+  static uint8_t incoming=0;
+  static uint32_t prev_ms=0;
+  uint32_t now_ms;
+  uint8_t n, val;
+
+  val = digitalRead(DataPin);
+  now_ms = millis();
+  if (now_ms - prev_ms > 250) {
+    bitcount = 0;
+    incoming = 0;
+  }
+  prev_ms = now_ms;
+  n = bitcount - 1;
+  if (n <= 7) {
+    incoming |= (val << n);
+  }
+  bitcount++;
+  if (bitcount == 11) {
+    uint8_t i = head + 1;    
+    if (i == BUFFER_SIZE) i = 0;
+    if (i != tail) {
+      buffer[i] = incoming;
+      head = i;
+    }
+    bitcount = 0;
+    incoming = 0;
+  }
+}
+
+bool PS2Driver::available() {
+  if (head == tail)
+    return false;
+
+  uint8_t i = tail+1;
+  if (i == BUFFER_SIZE) i = 0;
+  if (buffer[i] == 0xf0)
+    return i != head;
+  return true;
+}
+
+bool PS2Driver::isbreak() {
+  bool b = isbrk;
+  isbrk = false;
+  return b;
+}
+
+int PS2Driver::read() {
+  if (head == tail)
+    return -1;
+
+  uint8_t i = tail+1;
+  if (i == BUFFER_SIZE) i = 0;
+  tail = i;
+  if (buffer[i] == 0xf0) {
+    isbrk = true;
+    return read();
+  }
+  return buffer[i];
+}
+
+void PS2Driver::begin(uint8_t data_pin, uint8_t irq_pin)
+{
+  DataPin = data_pin;
+  pinMode(irq_pin, INPUT_PULLUP);
+  pinMode(data_pin, INPUT_PULLUP);
+  attachInterrupt(irq_pin, ps2interrupt, FALLING);
+  head = tail = 0;
+}
diff --git a/ps2drv.h b/ps2drv.h
new file mode 100644
index 0000000..65c8019
--- /dev/null
+++ b/ps2drv.h
@@ -0,0 +1,46 @@
+#ifndef __PS2DRV_H
+#define __PS2DRV_H
+
+class PS2Driver
+{
+  public:
+    PS2Driver() {}
+    
+    /**
+     * Starts the keyboard "service" by registering the external interrupt.
+     * setting the pin modes correctly and driving those needed to high.
+     * The propably best place to call this method is in the setup routine.
+     */
+    void begin(uint8_t dataPin, uint8_t irq_pin);
+
+    /**
+     * Returns true if there is a char to be read, false if not.
+     */
+    bool available();
+  
+    /**
+     * returns true if the key has been released
+     */
+    bool isbreak();
+    
+    /**
+     * Returns the scancode last received from the keyboard.
+     * If there is no char available, -1 is returned.
+     */
+    int read();
+};
+
+#define PS2_F1  0x05
+#define PS2_F2  0x06
+#define PS2_F3  0x04
+#define PS2_F4  0x0C
+#define PS2_F5  0x03
+#define PS2_F6  0x0B
+#define PS2_F7  0x83
+#define PS2_F8  0x0A
+#define PS2_F9  0x01
+#define PS2_F10  0x09
+#define PS2_F11  0x78
+#define PS2_F12  0x07
+
+#endif
diff --git a/r6502.cpp b/r6502.cpp
new file mode 100644
index 0000000..0bcd739
--- /dev/null
+++ b/r6502.cpp
@@ -0,0 +1,264 @@
+#include <stdio.h>
+#include <Stream.h>
+
+#include "memory.h"
+#include "cpu.h"
+#include "r6502.h"
+
+Memory::address r6502::run (unsigned clocks) {
+  while (clocks--) 
+  {
+    byte op = (*_memory)[PC];
+#ifdef CPU_DEBUG
+    _status ("%04x: %02x [%02x %02x %02x, %02x]\r", PC, op, A, X, Y, flags());
+#endif
+    PC++;
+    (this->*_ops[op])();
+  }
+  return PC;
+}
+
+byte r6502::flags() {
+  P.bits.N = ((N & 0x80) != 0);
+  P.bits.V = V;
+  P.bits.Z = !Z;
+  P.bits.C = C;
+  P.bits._ = 1;
+  return P.value;
+}
+
+char *r6502::status () {
+  static char buf[128];
+  flags();
+  sprintf (buf, "aa xx yy sp nv_bdizc  _pc_\r\n"
+     "%02x %02x %02x %02x %d%d%d%d%d%d%d%d  %04x\r\n", 
+     A, X, Y, S, P.bits.N, P.bits.V, P.bits._, P.bits.B, 
+     P.bits.D, P.bits.I, P.bits.Z, P.bits.C, PC);
+  return buf;
+}
+
+void r6502::checkpoint(Stream &s)
+{
+  s.write(PC / 0xff);
+  s.write(PC % 0xff);
+  s.write(S);  
+  s.write(A);  
+  s.write(X);  
+  s.write(Y);  
+  s.write(N);  
+  s.write(V);  
+  s.write(B);  
+  s.write(D);  
+  s.write(I);  
+  s.write(Z);  
+  s.write(C);  
+  s.write(P.value);  
+}
+
+void r6502::restore(Stream &s)
+{
+  byte hi = s.read(), lo = s.read();
+  PC = hi * 0xff + lo;
+  S = s.read();
+  A = s.read();
+  X = s.read();
+  Y = s.read();
+  N = s.read();
+  V = s.read();
+  B = s.read();
+  D = s.read();
+  I = s.read();
+  Z = s.read();
+  C = s.read();
+  P.value = s.read();
+}
+
+void r6502::raise (int level) {
+  if (level < 0)
+    nmi ();
+  else if (!P.bits.I)
+    irq ();
+  else
+    _irq = true;
+}
+
+void r6502::irq () {
+  pusha (PC);
+  P.bits.B = 0;
+  pushb (flags ());
+  P.bits.B = 1;
+  P.bits.I = 1;
+  PC = vector (ibvec);
+  _irq = false;
+}
+
+void r6502::brk () {
+  if (!P.bits.I) {
+    pusha (PC);
+    P.bits.B = 1;
+    php ();
+    P.bits.I = 1;
+    PC = vector (ibvec);
+  }
+  P.bits.B = 1;
+  P.bits._ = 1;
+}
+
+void r6502::rti () {
+  plp ();
+  PC = popa ();
+}
+
+void r6502::cli () {
+  P.bits.I = 0;
+  if (_irq)
+    irq();
+}
+
+void r6502::nmi () {
+  pusha (PC);
+  php ();
+  P.bits.I = 1;
+  PC = vector (nmivec);
+}
+
+// php and plp are complicated by the representation
+// of the processor state for efficient normal operation
+void r6502::php () {
+  P.bits.B = 1;
+  pushb (flags ());
+}
+
+void r6502::plp () {
+  P.value = popb ();
+  N = P.bits.N? 0x80: 0;
+  V = P.bits.V;
+  Z = !P.bits.Z;
+  C = P.bits.C;
+}
+
+void r6502::rts () {
+  PC = popa ()+1;
+}
+
+void r6502::jsr () {
+  pusha (PC+1);
+  PC = vector (PC);
+}
+
+void r6502::_adc (byte d) {
+  if (P.bits.D) {
+    int r = _fromBCD[A] + _fromBCD[d] + C;
+    C = (r > 99);
+    if (C) r -= 100;
+    A = _toBCD[r];
+  } else {
+    unsigned short u = (unsigned short)A + (unsigned short)d + (unsigned short)C;
+    short s = (char)A + (char)d + (char)C;
+    C = (u < 0 || u > 255);
+    V = (s > 127 || s < -128);
+    A = (u & 0xff);
+  }
+  N = (A & 0x80);
+  Z = A;
+}
+
+void r6502::sbcd (byte d) {
+  int r = _fromBCD[A] - _fromBCD[d] - !C;
+  C = (r >= 0);
+  if (r < 0) r += 100;
+  A = _toBCD[r & 0xff];
+  N = (A & 0x80);
+  Z = A;
+  // V not tested for: http://www.6502.org/tutorials/decimal_mode.html
+}
+
+void r6502::ill () {
+  _status ("Illegal instruction at %04x!\r\n%s", (PC-1), status());
+  longjmp (*_err, 1);
+}
+
+void r6502::reset ()
+{
+  P.value = 0;
+  P.bits._ = 1;
+  P.bits.B = 1;
+  _irq = false;
+  S = 0xff;
+  PC = vector(resvec);
+}
+
+r6502::r6502 (Memory *m, jmp_buf *e, CPU::statfn s): CPU (m,e,s) {
+
+  for (int i=0; i < 256; i++) {
+    _fromBCD[i] = ((i >> 4) & 0x0f)*10 + (i & 0x0f);
+    _toBCD[i] = (((i % 100) / 10) << 4) | (i % 10);
+  }
+    
+  OP *p = _ops;
+  *p++=&r6502::brk; *p++=&r6502::ora_ix; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::ora_z; *p++=&r6502::asl_z; *p++=&r6502::ill;
+  *p++=&r6502::php; *p++=&r6502::ora_; *p++=&r6502::asl; *p++=&r6502::ill; 
+  *p++=&r6502::nop3; *p++=&r6502::ora_a; *p++=&r6502::asl_a; *p++=&r6502::ill;
+  *p++=&r6502::bpl; *p++=&r6502::ora_iy; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::ora_zx; *p++=&r6502::asl_zx; *p++=&r6502::ill;
+  *p++=&r6502::clc; *p++=&r6502::ora_ay; *p++=&r6502::nop; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::ora_ax; *p++=&r6502::asl_ax; *p++=&r6502::ill;
+  *p++=&r6502::jsr; *p++=&r6502::and_ix; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::bit_z; *p++=&r6502::and_z; *p++=&r6502::rol_z; *p++=&r6502::ill;
+  *p++=&r6502::plp; *p++=&r6502::and_; *p++=&r6502::rol; *p++=&r6502::ill; 
+  *p++=&r6502::bit_a; *p++=&r6502::and_a; *p++=&r6502::rol_a; *p++=&r6502::ill;
+  *p++=&r6502::bmi; *p++=&r6502::and_iy; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::and_zx; *p++=&r6502::rol_zx; *p++=&r6502::ill;
+  *p++=&r6502::sec; *p++=&r6502::and_ay; *p++=&r6502::nop; *p++=&r6502::ill; 
+  *p++=&r6502::nop3; *p++=&r6502::and_ax; *p++=&r6502::rol_ax; *p++=&r6502::ill;
+  *p++=&r6502::rti; *p++=&r6502::eor_ix; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::eor_z; *p++=&r6502::lsr_z; *p++=&r6502::ill;
+  *p++=&r6502::pha; *p++=&r6502::eor_; *p++=&r6502::lsr_; *p++=&r6502::ill; 
+  *p++=&r6502::jmp; *p++=&r6502::eor_a; *p++=&r6502::lsr_a; *p++=&r6502::ill;
+  *p++=&r6502::bvc; *p++=&r6502::eor_iy; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::eor_zx; *p++=&r6502::lsr_zx; *p++=&r6502::ill;
+  *p++=&r6502::cli; *p++=&r6502::eor_ay; *p++=&r6502::nop; *p++=&r6502::ill; 
+  *p++=&r6502::nop3; *p++=&r6502::eor_ax; *p++=&r6502::lsr_ax; *p++=&r6502::ill;
+  *p++=&r6502::rts; *p++=&r6502::adc_ix; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::adc_z; *p++=&r6502::ror_z; *p++=&r6502::ill;
+  *p++=&r6502::pla; *p++=&r6502::adc_; *p++=&r6502::ror_; *p++=&r6502::ill; 
+  *p++=&r6502::jmp_i; *p++=&r6502::adc_a; *p++=&r6502::ror_a; *p++=&r6502::ill;
+  *p++=&r6502::bvs; *p++=&r6502::adc_iy; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::adc_zx; *p++=&r6502::ror_zx; *p++=&r6502::ill;
+  *p++=&r6502::sei; *p++=&r6502::adc_ay; *p++=&r6502::nop; *p++=&r6502::ill; 
+  *p++=&r6502::nop3; *p++=&r6502::adc_ax; *p++=&r6502::ror_ax; *p++=&r6502::ill;
+  *p++=&r6502::nop2; *p++=&r6502::sta_ix; *p++=&r6502::nop2; *p++=&r6502::ill; 
+  *p++=&r6502::sty_z; *p++=&r6502::sta_z; *p++=&r6502::stx_z; *p++=&r6502::ill;
+  *p++=&r6502::dey; *p++=&r6502::nop2; *p++=&r6502::txa; *p++=&r6502::ill; 
+  *p++=&r6502::sty_a; *p++=&r6502::sta_a; *p++=&r6502::stx_a; *p++=&r6502::ill;
+  *p++=&r6502::bcc; *p++=&r6502::sta_iy; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::sty_zx; *p++=&r6502::sta_zx; *p++=&r6502::stx_zy; *p++=&r6502::ill;
+  *p++=&r6502::tya; *p++=&r6502::sta_ay; *p++=&r6502::txs; *p++=&r6502::ill; 
+  *p++=&r6502::ill; *p++=&r6502::sta_ax; *p++=&r6502::ill; *p++=&r6502::ill;
+  *p++=&r6502::ldy_; *p++=&r6502::lda_ix; *p++=&r6502::ldx_; *p++=&r6502::lax_ix; 
+  *p++=&r6502::ldy_z; *p++=&r6502::lda_z; *p++=&r6502::ldx_z; *p++=&r6502::lax_z;
+  *p++=&r6502::tay; *p++=&r6502::lda_; *p++=&r6502::tax; *p++=&r6502::ill; 
+  *p++=&r6502::ldy_a; *p++=&r6502::lda_a; *p++=&r6502::ldx_a; *p++=&r6502::lax_a;
+  *p++=&r6502::bcs; *p++=&r6502::lda_iy; *p++=&r6502::ill; *p++=&r6502::lax_iy; 
+  *p++=&r6502::ldy_zx; *p++=&r6502::lda_zx; *p++=&r6502::ldx_zy; *p++=&r6502::lax_zy;
+  *p++=&r6502::clv; *p++=&r6502::lda_ay; *p++=&r6502::tsx; *p++=&r6502::ill; 
+  *p++=&r6502::ldy_ax; *p++=&r6502::lda_ax; *p++=&r6502::ldx_ay; *p++=&r6502::lax_ay;
+  *p++=&r6502::cpy_; *p++=&r6502::cmp_ix; *p++=&r6502::nop2; *p++=&r6502::ill; 
+  *p++=&r6502::cpy_z; *p++=&r6502::cmp_z; *p++=&r6502::dec_z; *p++=&r6502::ill;
+  *p++=&r6502::iny; *p++=&r6502::cmp_; *p++=&r6502::dex; *p++=&r6502::ill; 
+  *p++=&r6502::cpy_a; *p++=&r6502::cmp_a; *p++=&r6502::dec_a; *p++=&r6502::ill;
+  *p++=&r6502::bne; *p++=&r6502::cmp_iy; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::cmp_zx; *p++=&r6502::dec_zx; *p++=&r6502::ill;
+  *p++=&r6502::cld; *p++=&r6502::cmp_ay; *p++=&r6502::nop; *p++=&r6502::ill; 
+  *p++=&r6502::nop3; *p++=&r6502::cmp_ax; *p++=&r6502::dec_ax; *p++=&r6502::ill;
+  *p++=&r6502::cpx_; *p++=&r6502::sbc_ix; *p++=&r6502::nop2; *p++=&r6502::ill; 
+  *p++=&r6502::cpx_z; *p++=&r6502::sbc_z; *p++=&r6502::inc_z; *p++=&r6502::ill;
+  *p++=&r6502::inx; *p++=&r6502::sbc_; *p++=&r6502::nop; *p++=&r6502::ill; 
+  *p++=&r6502::cpx_a; *p++=&r6502::sbc_a; *p++=&r6502::inc_a; *p++=&r6502::ill;
+  *p++=&r6502::beq; *p++=&r6502::sbc_iy; *p++=&r6502::ill; *p++=&r6502::ill; 
+  *p++=&r6502::nop2; *p++=&r6502::sbc_zx; *p++=&r6502::inc_zx; *p++=&r6502::ill;
+  *p++=&r6502::sed; *p++=&r6502::sbc_ay; *p++=&r6502::nop; *p++=&r6502::ill; 
+  *p++=&r6502::nop3; *p++=&r6502::sbc_ax; *p++=&r6502::inc_ax; *p++=&r6502::ill;
+}
+
diff --git a/r6502.h b/r6502.h
new file mode 100644
index 0000000..ebf66b6
--- /dev/null
+++ b/r6502.h
@@ -0,0 +1,316 @@
+/*
+ * r6502.h
+ */
+#ifndef _R6502_H
+#define _R6502_H
+
+#undef PC
+class Stream;
+
+class r6502: public CPU {
+public:
+  void raise(int);
+  void reset();
+  Memory::address run(unsigned);
+  char *status();
+  void checkpoint(Stream &);
+  void restore(Stream &);
+
+  r6502 (Memory *, jmp_buf *, CPU::statfn);
+private:
+  /* registers */
+  Memory::address PC;
+  byte S, A, X, Y;
+  byte N, V, B, D, I, Z, C;
+  union {
+    struct {
+      unsigned C:1;
+      unsigned Z:1;
+      unsigned I:1;
+      unsigned D:1;
+      unsigned B:1;
+      unsigned _:1;           // unused
+      unsigned V:1;
+      unsigned N:1;
+    } bits;
+    byte value;
+  } P;
+  byte _toBCD[256], _fromBCD[256];  // BCD maps
+  bool _irq;        // interrupt pending
+
+  void irq();
+  void nmi();
+  byte flags();
+
+  /* stack */
+  inline void pusha (Memory::address ret) {
+    (*_memory)[0x0100+S--] = ret >> 8;
+    (*_memory)[0x0100+S--] = ret & 0xff;
+  }
+
+  inline void pushb (byte b) {
+    (*_memory)[0x0100+S--] = b;
+  }
+
+  inline byte popb () {
+    return (*_memory)[++S+0x0100];
+  }
+
+  inline Memory::address popa () {
+    byte b = popb ();
+    return ((popb () << 8) | b);
+  }
+
+  static const Memory::address nmivec = 0xfffa;
+  static const Memory::address resvec = 0xfffc;
+  static const Memory::address ibvec = 0xfffe;
+  
+  inline Memory::address vector(Memory::address v) {
+    return ((*_memory)[v+1] << 8) | (*_memory)[v];
+  }
+
+  /* operators */
+  inline void _cmp (byte a) { Z=N=A-a; C=(A>=a); }
+  inline void _cpx (byte a) { Z=N=X-a; C=(X>=a); }
+  inline void _cpy (byte a) { Z=N=Y-a; C=(Y>=a); }
+  inline void _and (byte a) { Z=N=A&=a; }
+  inline void _eor (byte a) { Z=N=A^=a; }
+  inline void _ora (byte a) { Z=N=A|=a; }
+  inline void _lda (byte a) { Z=N=A=a; }
+  inline void _ldx (byte a) { Z=N=X=a; }
+  inline void _ldy (byte a) { Z=N=Y=a; }
+
+  /* modes */
+  inline Memory::address _a () { 
+    Memory::address a = (*_memory)[PC++];
+    return a | ((*_memory)[PC++] << 8);
+  }
+  inline Memory::address _ax () { return _a()+X; }
+  inline Memory::address _ay () { return _a()+Y; }
+  inline Memory::address _z () { return (*_memory)[PC++]; }
+  inline Memory::address _zx () { return (_z()+X) & 0xff; }
+  inline Memory::address _zy () { return (_z()+Y) & 0xff; }
+  inline Memory::address _i (Memory::address a) { 
+    return ((*_memory)[a+1]<<8)|(*_memory)[a]; 
+  }
+  inline Memory::address _ix () { return _i(_zx()); }
+  inline Memory::address _iy () { return _i((*_memory)[PC++])+Y; }
+
+  void _adc (byte a);
+  void _sbc (byte a) { if (P.bits.D) sbcd(a); else _adc(~a); }
+  void sbcd (byte a);
+
+  inline byte __ror (byte b) {
+    N=b>>1; if (C) N|=0x80; C=b&1; return Z=N;
+  }
+  inline void _ror (Memory::address a) {
+    (*_memory)[a] = __ror((*_memory)[a]);
+  }
+  inline byte __rol (byte b) {
+    N=b<<1; if (C) N|=1; C=(b&0x80)!=0; return Z=N;
+  }
+  inline void _rol (Memory::address a) {
+    (*_memory)[a] = __rol((*_memory)[a]);
+  }
+  inline byte __asl (byte b) { C=(b&0x80)!=0; return Z=N=b<<1; }
+  inline void _asl (Memory::address a) {
+    (*_memory)[a] = __asl((*_memory)[a]);
+  }
+  inline byte __lsr (byte b) { C=b&1; Z=b>>1; N=0; return Z; }
+  inline void _lsr (Memory::address a) {
+    (*_memory)[a] = __lsr((*_memory)[a]);
+  }
+  inline void _inc (Memory::address a) {
+    Z=N=1+(*_memory)[a]; (*_memory)[a]=Z;
+  }
+  inline void _dec (Memory::address a) {
+    Z=N=(*_memory)[a]-1; (*_memory)[a]=Z;
+  }
+  inline void _bit (byte z) { V=((z & 0x40)!=0); N=(z & 0x80); Z=(A & z); }
+  inline void _bra() {
+    byte b = (*_memory)[PC];
+    PC += b;
+    if (b > 127) PC -= 0x0100;
+  }
+
+  /* dispatch table */
+  typedef void (r6502::*OP)(); OP _ops[256];
+
+  /* operations */
+  void brk ();
+  void ora_ix () { _ora ((*_memory)[_ix()]); }
+  void ill ();
+  void nop2 () { PC++; }
+  void ora_z () { _ora ((*_memory)[_z()]); }
+  void asl_z () { _asl (_z()); }
+  void php ();
+  void ora_ () { _ora ((*_memory)[PC++]); }
+  void asl () { C=(A&0x80)!=0; Z=N=A<<=1; }
+  void nop3 () { PC+=2; }
+  void ora_a () { _ora ((*_memory)[_a()]); }
+  void asl_a () { _asl (_a()); }
+  // 10
+  void bpl () { if (!(N & 0x80)) _bra(); PC++; }
+  void ora_iy () { _ora ((*_memory)[_iy()]); }
+  void ora_zx () { _ora ((*_memory)[_zx()]); }
+  void asl_zx () { _asl (_zx()); }
+  void clc () { C=0; }
+  void ora_ay () { _ora ((*_memory)[_ay()]); }
+  void nop () { }
+  void ora_ax () { _ora ((*_memory)[_ax()]); }
+  void asl_ax () { _asl (_ax()); }
+  // 20
+  void jsr ();
+  void and_ix () { _and ((*_memory)[_ix()]); }
+  void bit_z () { _bit ((*_memory)[_z()]); }
+  void and_z () { _and ((*_memory)[_z()]); }
+  void rol_z () { _rol (_z()); }
+  void plp ();
+  void and_ () { _and ((*_memory)[PC++]); }
+  void rol () { A=__rol (A); }
+  void bit_a () { _bit ((*_memory)[_a()]); }
+  void and_a () { _and ((*_memory)[_a()]); }
+  void rol_a () { _rol (_a()); }
+  // 30
+  void bmi () { if (N & 0x80) _bra(); PC++; }
+  void and_iy () { _and ((*_memory)[_iy()]); }
+  void and_zx () { _and ((*_memory)[_zx()]); }
+  void rol_zx () { _rol (_zx()); }
+  void sec () { C=1; }
+  void and_ay () { _and ((*_memory)[_ay()]); }
+  void and_ax () { _and ((*_memory)[_ax()]); }
+  void rol_ax () { _rol (_ax()); }
+  // 40
+  void rti ();
+  void eor_ix () { _eor ((*_memory)[_ix()]); }
+  void eor_z () { _eor ((*_memory)[_z()]); }
+  void lsr_z () { _lsr (_z()); }
+  void pha () { pushb (A); }
+  void eor_ () { _eor ((*_memory)[PC++]); }
+  void lsr_ () { A=__lsr(A); }
+  void jmp () { PC = _a (); }
+  void eor_a () { _eor ((*_memory)[_a()]); }
+  void lsr_a () { _lsr (_a()); }
+  // 50
+  void bvc () { if (!V) _bra(); PC++; }
+  void eor_iy () { _eor ((*_memory)[_iy()]); }
+  void eor_zx () { _eor ((*_memory)[_zx()]); }
+  void lsr_zx () { _lsr (_zx()); }
+  void cli ();
+  void eor_ay () { _eor ((*_memory)[_ay()]); }
+  void eor_ax () { _eor ((*_memory)[_ax()]); }
+  void lsr_ax () { _lsr (_ax()); }
+  // 60
+  void rts ();
+  void adc_ix () { _adc ((*_memory)[_ix()]); }
+  void adc_z () { _adc ((*_memory)[_z()]); }
+  void ror_z () { _ror (_z()); }
+  void pla () { Z=N=A=popb (); }
+  void adc_ () { _adc ((*_memory)[PC++]); }
+  void ror_ () { A=__ror (A); }
+  void jmp_i () { PC = _i(_a()); }
+  void adc_a () { _adc ((*_memory)[_a()]); }
+  void ror_a () { _ror (_a()); }
+  // 70
+  void bvs () { if (V) _bra(); PC++; }
+  void adc_iy () { _adc ((*_memory)[_iy()]); }
+  void adc_zx () { _adc ((*_memory)[_zx()]); }
+  void ror_zx () { _ror (_zx ()); }
+  void sei () { P.bits.I = 1; }
+  void adc_ay () { _adc ((*_memory)[_ay()]); }
+  void adc_ax () { _adc ((*_memory)[_ax()]); }
+  void ror_ax () { _ror (_ax ()); }
+  // 80
+  void sta_ix () { (*_memory)[_ix()] = A; }
+  void sty_z () { (*_memory)[_z()] = Y; }
+  void sta_z () { (*_memory)[_z()] = A; }
+  void stx_z () { (*_memory)[_z()] = X; }
+  void dey () { Z=N=--Y; }
+  void txa () { Z=N=A=X; }
+  void sty_a () { (*_memory)[_a()] = Y; }
+  void sta_a () { (*_memory)[_a()] = A; }
+  void stx_a () { (*_memory)[_a()] = X; }
+  // 90
+  void bcc () { if (!C) _bra(); PC++; }
+  void sta_iy () { (*_memory)[_iy()] = A; }
+  void sty_zx () { (*_memory)[_zx()] = Y; }
+  void sta_zx () { (*_memory)[_zx()] = A; }
+  void stx_zy () { (*_memory)[_zy()] = X; }
+  void tya () { Z=N=A=Y; }
+  void sta_ay () { (*_memory)[_ay()] = A; }
+  void txs () { S=X; }
+  void sta_ax () { (*_memory)[_ax()] = A; }
+  // a0
+  void ldy_ () { _ldy ((*_memory)[PC++]); }
+  void lda_ix () { _lda ((*_memory)[_ix()]); }
+  void ldx_ () { _ldx ((*_memory)[PC++]); }
+  void lax_ix () { lda_ix (); X=A; }
+  void ldy_z () { _ldy ((*_memory)[_z()]); }
+  void lda_z () { _lda ((*_memory)[_z()]); }
+  void ldx_z () { _ldx ((*_memory)[_z()]); }
+  void lax_z () { lda_z (); X=A; }
+  void tay () { Z=N=Y=A; }
+  void lda_ () { _lda ((*_memory)[PC++]); }
+  void tax () { Z=N=X=A; }
+  void ldy_a () { _ldy ((*_memory)[_a()]); }
+  void lda_a () { _lda ((*_memory)[_a()]); }
+  void ldx_a () { _ldx ((*_memory)[_a()]); }
+  void lax_a () { lda_a (); X=A; }
+  // b0
+  void bcs () { if (C) _bra(); PC++; }
+  void lda_iy () { _lda ((*_memory)[_iy()]); }
+  void lax_iy () { lda_iy (); X=A; }
+  void ldy_zx () { _ldy ((*_memory)[_zx()]); }
+  void lda_zx () { _lda ((*_memory)[_zx()]); }
+  void ldx_zy () { _ldx ((*_memory)[_zy()]); }
+  void lax_zy () { ldx_zy (); A=X; }
+  void clv () { V=0; }
+  void lda_ay () { _lda ((*_memory)[_ay()]); }
+  void tsx () { Z=N=X=S; }
+  void ldy_ax () { _ldy ((*_memory)[_ax()]); }
+  void lda_ax () { _lda ((*_memory)[_ax()]); }
+  void ldx_ay () { _ldx ((*_memory)[_ay()]); }
+  void lax_ay () { ldx_ay (); A=X; }
+  // c0
+  void cpy_ () { _cpy ((*_memory)[PC++]); }
+  void cmp_ix () { _cmp ((*_memory)[_ix()]); }
+  void cpy_z () { _cpy ((*_memory)[_z()]); }
+  void cmp_z () { _cmp ((*_memory)[_z()]); }
+  void dec_z () { _dec (_z()); }
+  void iny () { Z=N=++Y; }
+  void cmp_ () { _cmp ((*_memory)[PC++]); }
+  void dex () { Z=N=--X; }
+  void cpy_a () { _cpy ((*_memory)[_a()]); }
+  void cmp_a () { _cmp ((*_memory)[_a()]); }
+  void dec_a () { _dec (_a()); }
+  // d0
+  void bne () { if (Z) _bra(); PC++; }
+  void cmp_iy () { _cmp ((*_memory)[_iy()]); }
+  void cmp_zx () { _cmp ((*_memory)[_zx()]); }
+  void dec_zx () { _dec (_zx()); }
+  void cld () { P.bits.D = 0; }
+  void cmp_ay () { _cmp ((*_memory)[_ay()]); }
+  void cmp_ax () { _cmp ((*_memory)[_ax()]); }
+  void dec_ax () { _dec (_ax()); }
+  // e0
+  void cpx_ () { _cpx ((*_memory)[PC++]); }
+  void sbc_ix () { _sbc ((*_memory)[_ix()]); }
+  void cpx_z () { _cpx ((*_memory)[_z()]); }
+  void sbc_z () { _sbc ((*_memory)[_z()]); }
+  void inc_z () { _inc (_z()); }
+  void inx () { Z=N=++X; }
+  void sbc_ () { _sbc ((*_memory)[PC++]); }
+  void cpx_a () { _cpx ((*_memory)[_a()]); }
+  void sbc_a () { _sbc ((*_memory)[_a()]); }
+  void inc_a () { _inc (_a()); }
+  // f0
+  void beq () { if (!Z) _bra(); PC++; }
+  void sbc_iy () { _sbc ((*_memory)[_iy()]); }
+  void sbc_zx () { _sbc ((*_memory)[_zx()]); }
+  void inc_zx () { _inc (_zx()); }
+  void sed () { P.bits.D = 1; }
+  void sbc_ay () { _sbc ((*_memory)[_ay()]); }
+  void sbc_ax () { _sbc ((*_memory)[_ax()]); }
+  void inc_ax () { _inc (_ax()); }
+};
+#endif
diff --git a/r65emu.h b/r65emu.h
new file mode 100644
index 0000000..c5765d4
--- /dev/null
+++ b/r65emu.h
@@ -0,0 +1,13 @@
+#ifndef _R65EMU_H
+#define _R65EMU_H
+
+#include "memory.h"
+#include "cpu.h"
+#include "r6502.h"
+#include "ram.h"
+#include "spiram.h"
+#include "prom.h"
+#include "ps2drv.h"
+#include "hardware.h"
+
+#endif
diff --git a/ram.h b/ram.h
new file mode 100644
index 0000000..5ebd418
--- /dev/null
+++ b/ram.h
@@ -0,0 +1,17 @@
+#ifndef _RAM_H
+#define _RAM_H
+
+class ram: public Memory::Device {
+public:
+  virtual void operator= (byte c) { _mem[_acc] = c; }
+  virtual operator byte () { return _mem[_acc]; }
+
+  void checkpoint(Stream &s) { s.write(_mem, sizeof(_mem)); }
+  void restore(Stream &s) { s.readBytes((char *)_mem, sizeof(_mem)); }
+
+  ram (): Memory::Device(sizeof(_mem)) {}
+
+private:
+  byte _mem[1024];
+};
+#endif
diff --git a/spiram.cpp b/spiram.cpp
new file mode 100644
index 0000000..fff96c5
--- /dev/null
+++ b/spiram.cpp
@@ -0,0 +1,47 @@
+#include <SPI.h>
+#include <SpiRAM.h>
+#include "memory.h"
+#include "spiram.h"
+#include "hardware.h"
+
+extern SPIClass SPIRAM_DEV;
+
+SpiRAM spiRam(SPIRAM_DEV, SPIRAM_CS);
+
+void spiram::begin(byte cs, int module)
+{
+  SPI_for_SD.setModule(module);
+  SPI_for_SD.setClockDivider(SPI_CLOCK_DIV16);
+  SPI_for_SD.setDataMode(SPI_MODE0);
+  pinMode(PF_3, OUTPUT);
+  pinMode(cs, OUTPUT);
+}
+
+void spiram::operator=(byte b)
+{
+  spiRam.write_byte(_acc, b);
+}
+
+spiram::operator byte()
+{
+  return spiRam.read_byte(_acc);
+}
+
+void spiram::checkpoint(Stream &s)
+{
+  char buf[Memory::page_size];
+  for (int i = 0; i < pages(); i++) {
+    spiRam.read_stream(i * Memory::page_size, buf, sizeof(buf));
+    s.write((byte *)buf, sizeof(buf));
+  }
+}
+
+void spiram::restore(Stream &s)
+{
+  char buf[Memory::page_size];
+  for (int i = 0; i < pages(); i++) {
+    s.readBytes(buf, sizeof(buf));
+    spiRam.write_stream(i * Memory::page_size, buf, sizeof(buf));
+  }
+}
+
diff --git a/spiram.h b/spiram.h
new file mode 100644
index 0000000..a98683d
--- /dev/null
+++ b/spiram.h
@@ -0,0 +1,16 @@
+#ifndef __SPIRAM_H__
+#define __SPIRAM_H__
+
+class spiram: public Memory::Device {
+public:
+  virtual void operator= (byte c);
+  virtual operator byte ();
+
+  void checkpoint(Stream &s);
+  void restore(Stream &s);
+
+  spiram(int bytes): Memory::Device(bytes) {}
+  void begin(byte cs, int module);
+};
+
+#endif