blink cursor (#9)

* PIA cleanup

* move Apple1-dependent bits onto io class

* implement irq_a1 and irq_b1

* irq2 + cleanups

* ddr part 1

* ddr processing part 2

* ...

Apple1.ino

@@ -3,8 +3,8 @@
 
 #include <r65emu.h>
 #include <r6502.h>
+#include <pia.h>
 
-#include "pia.h"
 #include "io.h"
 #include "config.h"
 
@@ -34,7 +34,7 @@ void reset() {
 		io.status("Reset failed");
 		return;
 	}
-	io.files.start();
+	io.start();
 #if defined(KRUSADER)
 	io.status("Krusader: F000R / Basic: E000R");
 #else

TODO.md

@@ -1,11 +0,0 @@
-- more PIA: check out vice
-
-PIA init-sequence
-5021 > 12 7F
-5021 > 11 A7
-5022 > 13 A7
-5023 > 12 5C
-5025 > 12 D
-5026 > 12 0
-
-http://mamedev.org/source/src/mess/machine/apple1.c.html

io.cpp

@@ -1,22 +1,16 @@
-#include <Stream.h>
-#include <stdint.h>
+#include <Arduino.h>
 #include <memory.h>
 #include <display.h>
 #include <serialio.h>
 #include <filer.h>
 #include <keyboard.h>
+#include <pia.h>
 #include <timed.h>
 
-#include "pia.h"
 #include "io.h"
 #include "hardware.h"
 #include "config.h"
 
-#define ROWS	24
-#define COLS	40
-static unsigned r, c;
-static char screen[ROWS][COLS];
-
 void io::reset() {
 	Display::begin(BG_COLOUR, FG_COLOUR, ORIENT);
 	clear();
@@ -28,7 +22,29 @@ void io::reset() {
 			screen[j][i] = ' ';
 
 	_loading = false;
-	pia::reset();
+	PIA::reset();
+}
+
+static io *i;
+
+const int TICK_FREQ = 2;
+
+bool io::start() {
+
+	i = this;
+	timer_create(TICK_FREQ, io::on_tick);
+	return files.start();
+}
+
+void IRAM_ATTR io::on_tick() {
+
+	static int tick = 0;
+	tick = ++tick % 3;
+	i->cursor(tick < 2);
+}
+
+void io::cursor(bool on) {
+	draw(on? '_': ' ', c, r);
 }
 
 void io::load() {
@@ -78,13 +94,14 @@ static const uint8_t shiftmap[] PROGMEM = {
 };
 
 void io::down(uint8_t scan) {
-	set_porta(0);
 	if (isshift(scan))
 		_shift = true;
 }
 
 void io::enter(uint8_t key) {
-	set_porta(key + 0x80);
+	PIA::write_ca1(false);
+	PIA::write_porta_in(key + 0x80);
+	PIA::write_ca1(true);
 }
 
 void io::up(uint8_t scan) {
@@ -142,25 +159,21 @@ void io::display(uint8_t b) {
 void io::write_portb(uint8_t b) {
 	b &= 0x7f;
 	display(b);
-	pia::write_portb(b);
+	PIA::write_portb(b);
 }
 
-uint8_t io::read_porta_cr() {
-	uint8_t b = pia::read_porta_cr();
-	if (b != 0xa7)
-		return b;
-
+uint8_t io::read_cra() {
 	if (_loading) {
 		if (files.more())
 			enter(files.read());
 		else
 			_loading = false;
 	}
-	return b;
+	return PIA::read_cra();
 }
 
 void io::checkpoint(Stream &s) {
-	pia::checkpoint(s);
+	PIA::checkpoint(s);
 	s.write(r);
 	s.write(c);
 	for (int j = 0; j < ROWS; j++)
@@ -169,7 +182,7 @@ void io::checkpoint(Stream &s) {
 }
 
 void io::restore(Stream &s) {
-	pia::restore(s);
+	PIA::restore(s);
 	r = s.read();
 	c = s.read();
 	for (int j = 0; j < ROWS; j++)

io.h

@@ -1,30 +1,42 @@
 #ifndef _IO_H
 #define _IO_H
 
-// http://mamedev.org/source/src/mess/machine/apple1.c.html
-class io: public Display, Keyboard, public pia {
+class io: public Memory::Device, public Display, Keyboard, public PIA {
 public:
-	io(filer &files): files(files) {}
+	io(filer &files): Memory::Device(Memory::page_size), files(files) {}
 
-	virtual void reset();
-	virtual void down(uint8_t scan);
-	virtual void up(uint8_t scan);
+	void reset();
+	bool start();
 
-	virtual void checkpoint(Stream &);
-	virtual void restore(Stream &);
+	static void on_tick();
 
-	virtual void write_portb(uint8_t);
-	virtual uint8_t read_porta_cr();
+	void down(uint8_t);
+	void up(uint8_t);
+
+	void operator=(uint8_t b) { PIA::write(_acc, b); }
+	operator uint8_t() { return PIA::read(_acc); }
+
+	void checkpoint(Stream &);
+	void restore(Stream &);
+
+	void write_portb(uint8_t);
+	uint8_t read_cra();
 
 	void load();
 	filer &files;
+
+	static const uint8_t ROWS = 24;
+	static const uint8_t COLS = 40;
+
 private:
+	void cursor(bool on);
 	void display(uint8_t);
 	void draw(char, int, int);
 	void enter(uint8_t);
 
-	bool _shift;
-	bool _loading;
+	bool _shift, _loading;
+	uint8_t r, c;
+	char screen[ROWS][COLS];
 };
 
 #endif

pia.cpp

@@ -1,61 +0,0 @@
-#include <Arduino.h>
-#include <memory.h>
-#include "pia.h"
-
-void pia::operator=(uint8_t b) {
-#if defined(DEBUGGING)
-	Serial.print(millis());
-	Serial.print(" > ");
-	Serial.print(_acc, 16);
-	Serial.print(' ');
-	Serial.println(b, 16);
-#endif
-	switch(_acc % 4) {
-	case 0:
-		write_porta(b);
-		break;
-	case 1:
-		write_porta_cr(b);
-		break;
-	case 2:
-		write_portb(b);
-		break;
-	case 3:
-		write_portb_cr(b);
-		break;
-	}
-}
-
-pia::operator uint8_t() {
-#if defined(DEBUGGING)
-	Serial.print(millis());
-	Serial.print(" < ");
-	Serial.println(_acc, 16);
-#endif
-	switch (_acc % 4) {
-	case 0:
-		return read_porta();
-	case 1:
-		return read_porta_cr();
-	case 2:
-		return read_portb();
-	case 3:
-		return read_portb_cr();
-	}
-	return 0xff;
-}
-
-void pia::checkpoint(Stream &s) {
-	s.write(portb_cr);
-	s.write(portb);
-	s.write(porta_cr);
-	s.write(porta);
-}
-
-void pia::restore(Stream &s) {
-	portb_cr = s.read();
-	portb = s.read();
-	porta_cr = s.read();
-	porta = s.read();
-}
-

pia.h

@@ -1,51 +0,0 @@
-#ifndef __PIA_H__
-#define __PIA_H__
-
-class pia: public Memory::Device {
-public:
-	pia(): Memory::Device(256), portb_cr(0), porta_cr(0) {}
-	virtual void reset() { portb_cr = porta_cr = 0; }
-
-	void operator=(uint8_t);
-	operator uint8_t();
-
-	void checkpoint(Stream &);
-	void restore(Stream &);
-
-protected:
-	// write to the "external" side of the port
-	void set_porta(uint8_t b) {
-		porta = b;
-		if (b & 0x80)
-			porta_cr = 0xa7;
-	}
-
-	// "device-side" operations (called from memory interface)
-	uint8_t read_porta() { return porta; }
-	virtual uint8_t read_porta_cr() {
-		if (porta_cr & 0x80) {
-			porta_cr = 0;
-			return 0xa7;
-		}
-		return porta_cr;
-	}
-	uint8_t read_portb() { return portb; }
-	uint8_t read_portb_cr() { return portb_cr; }
-
-	void write_porta(uint8_t b) { porta = b; }
-	void write_porta_cr(uint8_t b) {
-		if (!(porta_cr & 0x80) && b >= 0x80)
-			porta_cr |= 0x80;
-		else
-			porta_cr = b;
-	}
-	virtual void write_portb(uint8_t b) { portb = b; }
-	void write_portb_cr(uint8_t b) {
-		if (portb_cr < 0x80)
-			portb_cr = b;
-	}
-
-private:
-	uint8_t portb_cr, portb, porta_cr, porta;
-};
-#endif