Merge pull request #44 from spicyjpeg/actions

GitHub Actions CI, psxcd and libc fixes, new examples

7 files changed, 484 insertions, 60 deletions

diff --git a/examples/io/pads/CMakeLists.txt b/examples/io/pads/CMakeLists.txt
index 5bd7f5d..cf5f817 100644
--- a/examples/io/pads/CMakeLists.txt
+++ b/examples/io/pads/CMakeLists.txt
@@ -3,10 +3,6 @@
 
 cmake_minimum_required(VERSION 3.20)
 
-if(NOT DEFINED CMAKE_TOOLCHAIN_FILE AND DEFINED ENV{PSN00BSDK_LIBS})
-	set(CMAKE_TOOLCHAIN_FILE $ENV{PSN00BSDK_LIBS}/cmake/sdk.cmake)
-endif()
-
 project(
 	pads
 	LANGUAGES    C ASM
diff --git a/examples/io/pads/main.c b/examples/io/pads/main.c
index 92beb1c..d100482 100644
--- a/examples/io/pads/main.c
+++ b/examples/io/pads/main.c
@@ -118,16 +118,16 @@ static volatile uint8_t  pad_buff[2][34];
 static volatile size_t   pad_buff_len[2];
 static volatile uint32_t pad_digital_only[2] = { 0, 0 };
 
-// Just a wrapper around spi_new_request(). This does not send the command
+// Just a wrapper around SPI_CreateRequest(). This does not send the command
 // immediately but adds it to the driver's request queue.
 void send_pad_cmd(
-	uint32_t    port,
-	PAD_COMMAND cmd,
-	uint8_t     arg1,
-	uint8_t     arg2,
-	SPICALLBACK callback
+	uint32_t     port,
+	PadCommand   cmd,
+	uint8_t      arg1,
+	uint8_t      arg2,
+	SPI_Callback callback
 ) {
-	SPIREQUEST *req = spi_new_request();
+	SPI_Request *req = SPI_CreateRequest();
 
 	req->len              = 9;
 	req->port             = port;
@@ -150,12 +150,12 @@ void send_pad_cmd(
 // actually a DualShock in digital mode by checking if it started identifying
 // as CONFIG_MODE after receiving a configuration command.
 void dualshock_init_cb(uint32_t port, const volatile uint8_t *buff, size_t rx_len) {
-	PADTYPE *pad = (PADTYPE *) buff;
+	PadResponse *pad = (PadResponse *) buff;
 
 	if (
 		(rx_len < 2) ||
-		(pad->raw.prefix != 0x5a) ||
-		(pad->raw.type != PAD_ID_CONFIG_MODE)
+		(pad->prefix != 0x5a) ||
+		(pad->type != PAD_ID_CONFIG_MODE)
 	) {
 		printf("no, pad is digital-only (len = %d)\n", rx_len);
 
@@ -187,7 +187,7 @@ void poll_cb(uint32_t port, const volatile uint8_t *buff, size_t rx_len) {
 	if (rx_len)
 		memcpy((void *) pad_buff[port], (void *) buff, rx_len);
 
-	PADTYPE *pad = (PADTYPE *) buff;
+	PadResponse *pad = (PadResponse *) buff;
 
 	// If this pad identifies as a digital pad and hasn't been flagged as a
 	// digital-only pad already, attempt to put it into analog mode by entering
@@ -196,8 +196,8 @@ void poll_cb(uint32_t port, const volatile uint8_t *buff, size_t rx_len) {
 	// returning digital pad responses.
 	if (
 		rx_len &&
-		(pad->raw.prefix == 0x5a) &&
-		(pad->raw.type == PAD_ID_DIGITAL)
+		(pad->prefix == 0x5a) &&
+		(pad->type == PAD_ID_DIGITAL)
 	) {
 		if (!pad_digital_only[port]) {
 			printf("Detecting if pad %d supports config mode... ", port + 1);
@@ -221,7 +221,7 @@ static CONTEXT ctx;
 
 int main(int argc, const char* argv[]) {
 	init_context(&ctx);
-	spi_init(&poll_cb);
+	SPI_Init(&poll_cb);
 
 	uint32_t counter = 0;
 
@@ -238,15 +238,14 @@ int main(int argc, const char* argv[]) {
 				continue;
 			}
 
-			PADTYPE    *pad = (PADTYPE *) pad_buff[port];
-			PAD_TYPEID type = pad->raw.type;
+			PadResponse *pad = (PadResponse *) pad_buff[port];
 
 			// According to nocash docs, there is a hardware bug in DualShock
 			// controllers that causes the prefix byte (normally 0x5a) to turn
 			// into 0x00 if the analog button is pressed after configuration
 			// commands have been used. Thus making sure the prefix is 0x5a
 			// isn't enough to reliably detect pads.
-			/*if ((pad->raw.prefix != 0x5a) && (type != PAD_ID_ANALOG)) {
+			/*if ((pad->prefix != 0x5a) && (pad->type != PAD_ID_ANALOG)) {
 				FntPrint(-1, "\n\nPORT %d: INVALID RESPONSE\n", port + 1);
 				if ((counter % 64) < 32)
 					FntPrint(-1, " CHECK CONNECTION...");
@@ -258,8 +257,8 @@ int main(int argc, const char* argv[]) {
 				-1,
 				"\n\nPORT %d: %s (TYPE=%d)\n",
 				port + 1,
-				PAD_TYPEIDS[type],
-				type
+				PAD_TYPEIDS[pad->type],
+				pad->type
 			);
 
 			// Print a hexdump of the payload returned by the pad.
diff --git a/examples/io/pads/spi.c b/examples/io/pads/spi.c
index e01b3f6..ef75ffc 100644
--- a/examples/io/pads/spi.c
+++ b/examples/io/pads/spi.c
@@ -54,21 +54,21 @@
 
 /* Internal structures and globals */
 
-typedef struct _SPICONTEXT {
-	uint8_t     tx_buff[SPI_BUFF_LEN];
-	uint8_t     rx_buff[SPI_BUFF_LEN];
-	uint32_t    tx_len, rx_len, port;
-	SPICALLBACK callback;
-} SPICONTEXT;
+typedef struct _SPI_CONTEXT {
+	uint8_t			tx_buff[SPI_BUFF_LEN];
+	uint8_t			rx_buff[SPI_BUFF_LEN];
+	uint32_t		tx_len, rx_len, port;
+	SPI_Callback	callback;
+} SPI_Context;
 
-static volatile SPICONTEXT          ctx;
-static volatile SPIREQUEST volatile *current_req;
-static SPICALLBACK                  default_cb;
+static volatile SPI_Context				ctx;
+static volatile SPI_Request volatile	*current_req;
+static SPI_Callback						default_cb;
 
 /* Request queue management */
 
-static void prepare_poll_req(void) {
-	PADREQUEST *req = (PADREQUEST *) ctx.tx_buff;
+static void _spi_create_poll_req(void) {
+	PadRequest *req = (PadRequest *) ctx.tx_buff;
 
 	req->addr     = 0x01;
 	req->cmd      = PAD_CMD_READ;
@@ -82,7 +82,7 @@ static void prepare_poll_req(void) {
 	ctx.callback = default_cb;
 }
 
-static void prepare_next_req(void) {
+static void _spi_next_req(void) {
 	// Copy the contents of the first request in the queue into the TX buffer.
 	memcpy((void *) ctx.tx_buff, (void *) current_req->data, current_req->len);
 
@@ -93,7 +93,7 @@ static void prepare_next_req(void) {
 
 	// Pop the first request from the queue by deallocating it and adjusting
 	// the pointer to the first queue item.
-	SPIREQUEST *next = current_req->next;
+	SPI_Request *next = current_req->next;
 
 	free((void *) current_req);
 	current_req = next;
@@ -101,7 +101,7 @@ static void prepare_next_req(void) {
 
 /* Interrupt handlers */
 
-static void poll_timer_tick(void) {
+static void _spi_poll_irq_handler(void) {
 	// Fetch the last response byte, which wasn't followed by a pulse on /ACK,
 	// from the RX FIFO.
 	if (JOY_STAT & 0x0002)
@@ -112,9 +112,9 @@ static void poll_timer_tick(void) {
 
 	// If the request queue is empty, create a pad polling request.
 	if (current_req)
-		prepare_next_req();
+		_spi_next_req();
 	else
-		prepare_poll_req();
+		_spi_create_poll_req();
 
 	// Prepare the SPI port by clearing any pending IRQ, pulling /CS high and
 	// enabling the /ACK IRQ. In order to communicate with controllers, /CS has
@@ -132,7 +132,7 @@ static void poll_timer_tick(void) {
 	JOY_TXRX = ctx.tx_buff[0];
 }
 
-static void spi_ack_handler(void) {
+static void _spi_ack_irq_handler(void) {
 	// Wait until /ACK is pulled up by the controller before sending the next
 	// byte. According to nocash docs, this has to be done before resetting the
 	// IRQ.
@@ -166,8 +166,8 @@ static void spi_ack_handler(void) {
 
 /* Public API */
 
-SPIREQUEST *spi_new_request(void) {
-	SPIREQUEST *req = malloc(sizeof(SPIREQUEST));
+SPI_Request *SPI_CreateRequest(void) {
+	SPI_Request *req = malloc(sizeof(SPI_Request));
 
 	req->len      = 0;
 	req->port     = 0;
@@ -179,7 +179,7 @@ SPIREQUEST *spi_new_request(void) {
 	if (!current_req) {
 		current_req = req;
 	} else {
-		volatile SPIREQUEST *volatile last = current_req;
+		volatile SPI_Request *volatile last = current_req;
 		while (last->next)
 			last = last->next;
 
@@ -189,7 +189,7 @@ SPIREQUEST *spi_new_request(void) {
 	return req;
 }
 
-void spi_set_poll_rate(uint32_t value) {
+void SPI_SetPollRate(uint32_t value) {
 	TIM_CTRL(2) = 0x0258; // CLK/8 input, IRQ on reload, disable one-shot IRQ
 
 	if (value < 65)
@@ -198,21 +198,21 @@ void spi_set_poll_rate(uint32_t value) {
 		TIM_RELOAD(2) = (F_CPU / 8) / value;
 }
 
-void spi_init(SPICALLBACK callback) {
+void SPI_Init(SPI_Callback callback) {
 	// Disable the BIOS timer handler (which for some stupid reason is enabled
 	// by default, even though it does nothing) and set up custom interrupt
 	// handlers.
 	EnterCriticalSection();
 	ChangeClearRCnt(2, 0);
-	InterruptCallback(6, &poll_timer_tick);
-	InterruptCallback(7, &spi_ack_handler);
+	InterruptCallback(6, &_spi_poll_irq_handler);
+	InterruptCallback(7, &_spi_ack_irq_handler);
 	ExitCriticalSection();
 
 	JOY_CTRL = 0x0040; // Reset all registers
 	JOY_MODE = 0x000d; // 1x multiplier, 8 data bits, no parity
 	JOY_BAUD = 0x0088; // 250000 bps
 
-	spi_set_poll_rate(250);
+	SPI_SetPollRate(250);
 	current_req = 0;
 	default_cb  = callback;
 }
diff --git a/examples/io/pads/spi.h b/examples/io/pads/spi.h
index 1c473cd..c50e065 100644
--- a/examples/io/pads/spi.h
+++ b/examples/io/pads/spi.h
@@ -9,23 +9,24 @@
 #include <stdint.h>
 #include <psxpad.h>
 
+// Maximum request/response length (34 bytes for pads, 140 for memory cards)
 //#define SPI_BUFF_LEN 34
 #define SPI_BUFF_LEN 140
 
 /* Request structures */
 
-typedef void (*SPICALLBACK)(uint32_t port, const volatile uint8_t *buff, size_t rx_len);
+typedef void (*SPI_Callback)(uint32_t port, const volatile uint8_t *buff, size_t rx_len);
 
-typedef struct _SPIREQUEST {
+typedef struct _SPI_Request {
 	union {
-		uint8_t        data[SPI_BUFF_LEN];
-		PADREQUEST     pad_req;
-		MCDREQUEST     mcd_req;
+		uint8_t			data[SPI_BUFF_LEN];
+		PadRequest		pad_req;
+		MemCardRequest	mcd_req;
 	};
-	uint32_t           len, port;
-	SPICALLBACK        callback;
-	struct _SPIREQUEST *next;
-} SPIREQUEST;
+	uint32_t			len, port;
+	SPI_Callback		callback;
+	struct _SPI_Request	*next;
+} SPI_Request;
 
 /* Public API */
 
@@ -34,7 +35,7 @@ typedef struct _SPIREQUEST {
  * object must be populated afterwards by setting the length, callback and
  * filling in the TX data buffer.
  */
-SPIREQUEST *spi_new_request(void);
+SPI_Request *SPI_CreateRequest(void);
 
 /**
  * @brief Changes the controller polling rate. The lowest supported rate is 65
@@ -43,7 +44,7 @@ SPIREQUEST *spi_new_request(void);
  *
  * @param value
  */
-void spi_set_poll_rate(uint32_t value);
+void SPI_SetPollRate(uint32_t value);
 
 /**
  * @brief Installs the SPI and timer 2 interrupt handlers and starts the poll
@@ -56,6 +57,6 @@ void spi_set_poll_rate(uint32_t value);
  *
  * @param callback
  */
-void spi_init(SPICALLBACK callback);
+void SPI_Init(SPI_Callback callback);
 
 #endif
diff --git a/examples/io/system573/CMakeLists.txt b/examples/io/system573/CMakeLists.txt
new file mode 100644
index 0000000..1c74347
--- /dev/null
+++ b/examples/io/system573/CMakeLists.txt
@@ -0,0 +1,23 @@
+# PSn00bSDK example CMake script
+# (C) 2021 spicyjpeg - MPL licensed
+
+cmake_minimum_required(VERSION 3.21)
+
+project(
+	system573
+	LANGUAGES    C ASM
+	VERSION      1.0.0
+	DESCRIPTION  "PSn00bSDK Konami System 573 example"
+	HOMEPAGE_URL "http://lameguy64.net/?page=psn00bsdk"
+)
+
+file(GLOB _sources *.c *.s)
+psn00bsdk_add_executable(system573 STATIC ${_sources})
+psn00bsdk_add_cd_image(system573_iso system573 iso.xml DEPENDS system573)
+
+install(
+	FILES
+		${PROJECT_BINARY_DIR}/system573.bin
+		${PROJECT_BINARY_DIR}/system573.cue
+	TYPE BIN
+)
diff --git a/examples/io/system573/iso.xml b/examples/io/system573/iso.xml
new file mode 100644
index 0000000..09b4d85
--- /dev/null
+++ b/examples/io/system573/iso.xml
@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="utf-8"?>
+<iso_project
+	image_name="${CD_IMAGE_NAME}.bin"
+	cue_sheet="${CD_IMAGE_NAME}.cue"
+>
+	<track type="data">
+		<identifiers
+			system			="PLAYSTATION"
+			volume			="SYSTEM573"
+			volume_set		="SYSTEM573"
+			publisher		="MEIDOTEK"
+			data_preparer	="PSN00BSDK ${PSN00BSDK_VERSION}"
+			application		="PLAYSTATION"
+			copyright		="README.TXT;1"
+		/>
+
+		<directory_tree>
+			<!--
+				The System 573 BIOS does not parse SYSTEM.CNF, it always looks
+				for an executable named PSX.EXE. Note that this behavior can be
+				abused to make multi-system CDs with different executables for
+				PS1 and 573 (i.e. have both PSX.EXE and SYSTEM.CNF pointing to
+				a different executable).
+			-->
+			<!--<file name="SYSTEM.CNF"	type="data" source="${PROJECT_SOURCE_DIR}/system.cnf" />-->
+			<file name="PSX.EXE"	type="data" source="system573.exe" />
+			<file name="PSX.MAP"	type="data" source="system573.map" />
+
+			<dummy sectors="1024"/>
+		</directory_tree>
+	</track>
+
+	<!--<track type="audio" source="track2.wav" />-->
+</iso_project>
diff --git a/examples/io/system573/main.c b/examples/io/system573/main.c
new file mode 100644
index 0000000..a06c4e5
--- /dev/null
+++ b/examples/io/system573/main.c
@@ -0,0 +1,371 @@
+/*
+ * PSn00bSDK Konami System 573 example
+ * (C) 2021 spicyjpeg - MPL licensed
+ *
+ * This is a minimal example demonstrating how to target the Konami System 573
+ * using PSn00bSDK. The System 573 is a PS1-based arcade motherboard that
+ * powered various Konami arcade games throughout the late 1990s, most notably
+ * Dance Dance Revolution and other Bemani rhythm games. It came in several
+ * configurations, with slightly different I/O connectors depending on the game
+ * and two optional add-on modules (known as the "analog I/O" and "digital I/O"
+ * boards respectively) providing light control outputs and, in the case of the
+ * digital I/O board, MP3 audio playback.
+ *
+ * Unlike other arcade systems based on PS1 hardware, the 573 is mostly
+ * identical to a regular PS1, with almost all custom extensions mapped into
+ * the expansion port region at 0x1f000000. The major differences are:
+ *
+ * - RAM is 4 MB instead of 2, and VRAM is 2 MB instead of 1. It is recommended
+ *   *not* to use the additional memory to preserve PS1 compatibility.
+ *
+ * - The CD drive is replaced by a standard IDE/ATAPI drive (which most of the
+ *   time is going to be an aftermarket DVD drive, as the original drives the
+ *   system shipped with were prone to failure and couldn't read CD-Rs). This
+ *   also means the 573 has no support at all for XA audio playback, as XA is
+ *   not part of the CD-ROM specification implemented by IDE drives. CD audio
+ *   is supported by most IDE drives, but 573 units with the digital I/O board
+ *   installed have the 4-pin audio cable plugged into that instead of the
+ *   drive. The IDE bus is connected to IRQ10 and DMA5 (expansion port) instead
+ *   of IRQ2 and DMA3, which go unused.
+ *
+ * - The BIOS seems to have most file I/O APIs removed and exposes no functions
+ *   whatsoever for accessing the IDE drive or the filesystem on the disc. The
+ *   launcher/shell is completely different from Sony's shell and is capable of
+ *   loading an executable from the CD drive, a PCMCIA memory-mapped flash card
+ *   or the internal 16 MB flash memory.
+ *
+ * - The SPI controller bus seems to be left unconnected. Inputs are routed to
+ *   a JAMMA PCB edge connector and handled through two custom/relabeled chips,
+ *   which expose the inputs as memory-mapped registers. There is also a JVS
+ *   port (i.e. RS-485 serial bus wired to a USB-A connector, commonly used for
+ *   daisy-chaining peripherals in arcade cabinets) managed by a
+ *   microcontroller.
+ *
+ * - There is a "security cartridge" slot, which breaks out the serial port as
+ *   well as several GPIO pins. All security cartridge communication and DRM is
+ *   handled by games rather than by the BIOS, so a security cartridge is *not*
+ *   required to boot homebrew. Each game came with a different cartridge type;
+ *   many of them expose the serial port or provide additional game-specific
+ *   I/O connectors.
+ *
+ * Currently the only publicly available documentation for the custom registers
+ * is the System 573 MAME driver. Also keep in mind that the psxcd library does
+ * not yet support IDE drives, so the 573's drive can only be accessed by
+ * writing a custom ATAPI driver and ISO9660 parser (which is out of the scope
+ * of this example).
+ *
+ * https://github.com/mamedev/mame/blob/master/src/mame/drivers/ksys573.cpp
+ * https://github.com/mamedev/mame/blob/master/src/mame/machine/k573dio.cpp
+ */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <psxetc.h>
+#include <psxapi.h>
+#include <psxgpu.h>
+#include <psxpad.h>
+
+/* Register definitions */
+
+#define EXP1_ADDR		*((volatile uint32_t *) 0x1f801000)
+#define EXP1_CTRL		*((volatile uint32_t *) 0x1f801008)
+
+#define K573_IN0		*((volatile uint16_t *) 0x1f400000)
+#define K573_IN1_L		*((volatile uint16_t *) 0x1f400004)
+#define K573_IN1_H		*((volatile uint16_t *) 0x1f400006)
+#define K573_IN2		*((volatile uint16_t *) 0x1f400008)
+#define K573_IN3_L		*((volatile uint16_t *) 0x1f40000c)
+#define K573_IN3_H		*((volatile uint16_t *) 0x1f40000e)
+#define K573_BANK		*((volatile uint16_t *) 0x1f500000)
+#define K573_WATCHDOG	*((volatile uint16_t *) 0x1f5c0000)
+
+#define K573_IDE_CS0	((volatile uint16_t *) 0x1f480000)
+#define K573_IDE_CS1	((volatile uint16_t *) 0x1f4c0000)
+#define K573_RTC		((volatile uint16_t *) 0x1f620000)
+#define K573_IO_BOARD	((volatile uint16_t *) 0x1f640000)
+
+typedef enum {
+	ANALOG_IO_LIGHTS0	= 0x20,
+	ANALOG_IO_LIGHTS1	= 0x22,
+	ANALOG_IO_LIGHTS2	= 0x24,
+	ANALOG_IO_LIGHTS3	= 0x26,
+
+	// The digital I/O board has a lot more registers than these, but there
+	// seems to be no DIGITAL_IO_LIGHTS6 register. WTF
+	DIGITAL_IO_LIGHTS1	= 0x70,
+	DIGITAL_IO_LIGHTS0	= 0x71,
+	DIGITAL_IO_LIGHTS3	= 0x72,
+	DIGITAL_IO_LIGHTS7	= 0x73,
+	DIGITAL_IO_LIGHTS4	= 0x7d,
+	DIGITAL_IO_LIGHTS5	= 0x7e,
+	DIGITAL_IO_LIGHTS2	= 0x7f
+} IO_BOARD_REG;
+
+// The 573's real-time clock chip is an M48T58, which behaves like a standard
+// 8 KB battery-backed SRAM with a bunch of special registers. Official games
+// store highscores and settings in RTC RAM.
+typedef enum {
+	RTC_CTRL			= 0x1ff8,
+	RTC_SECONDS			= 0x1ff9,
+	RTC_MINUTES			= 0x1ffa,
+	RTC_HOURS			= 0x1ffb,
+	RTC_DAY_OF_WEEK		= 0x1ffc,
+	RTC_DAY_OF_MONTH	= 0x1ffd,
+	RTC_MONTH			= 0x1ffe,
+	RTC_YEAR			= 0x1fff
+} RTC_REG;
+
+#define btoi(x) ((((x) >> 4) & 0xf) * 10 + ((x) & 0xf))
+
+/* Display/GPU context utilities */
+
+#define SCREEN_XRES 320
+#define SCREEN_YRES 240
+
+#define BGCOLOR_R 48
+#define BGCOLOR_G 24
+#define BGCOLOR_B  0
+
+typedef struct {
+	DISPENV  disp;
+	DRAWENV  draw;
+} DB;
+
+typedef struct {
+	DB       db[2];
+	uint32_t db_active;
+} CONTEXT;
+
+void init_context(CONTEXT *ctx) {
+	DB *db;
+
+	ResetGraph(0);
+	ctx->db_active = 0;
+
+	db = &(ctx->db[0]);
+	SetDefDispEnv(&(db->disp),           0, 0, SCREEN_XRES, SCREEN_YRES);
+	SetDefDrawEnv(&(db->draw), SCREEN_XRES, 0, SCREEN_XRES, SCREEN_YRES);
+	setRGB0(&(db->draw), BGCOLOR_R, BGCOLOR_G, BGCOLOR_B);
+	db->draw.isbg = 1;
+	db->draw.dtd  = 1;
+
+	db = &(ctx->db[1]);
+	SetDefDispEnv(&(db->disp), SCREEN_XRES, 0, SCREEN_XRES, SCREEN_YRES);
+	SetDefDrawEnv(&(db->draw),           0, 0, SCREEN_XRES, SCREEN_YRES);
+	setRGB0(&(db->draw), BGCOLOR_R, BGCOLOR_G, BGCOLOR_B);
+	db->draw.isbg = 1;
+	db->draw.dtd  = 1;
+
+	PutDrawEnv(&(db->draw));
+	//PutDispEnv(&(db->disp));
+
+	// Create a text stream at the top of the screen.
+	FntLoad(960, 0);
+	FntOpen(8, 16, 304, 208, 2, 512);
+}
+
+void display(CONTEXT *ctx) {
+	DB *db;
+
+	DrawSync(0);
+	VSync(0);
+	ctx->db_active ^= 1;
+
+	db = &(ctx->db[ctx->db_active]);
+	PutDrawEnv(&(db->draw));
+	PutDispEnv(&(db->disp));
+	SetDispMask(1);
+}
+
+/* Input polling utilities */
+
+typedef struct {
+	uint8_t p1_joy, p1_btn;
+	uint8_t p2_joy, p2_btn;
+	uint8_t coin, dip_sw;
+} JAMMAInputs;
+
+void get_jamma_inputs(JAMMAInputs *output) {
+	uint16_t in1l = K573_IN1_L;
+	uint16_t in1h = K573_IN1_H;
+	uint16_t in2  = K573_IN2;
+	uint16_t in3l = K573_IN3_L;
+	uint16_t in3h = K573_IN3_H;
+	uint8_t  p1_btn, p2_btn, coin;
+
+	// Rearrange the bits read from the input register into something that's
+	// easier to parse and display. Refer to MAME for information on what each
+	// bit in the IN* registers does.
+	p1_btn  = ((in2  >> 15) & 0x0001);      // Bit 0   = start button
+	p1_btn |= ((in2  >>  8) & 0x0007) << 1; // Bit 1-3 = buttons 1-3
+	p1_btn |= ((in3l >>  8) & 0x0003) << 4; // Bit 4-5 = buttons 4-5
+	p1_btn |= ((in3l >> 11) & 0x0001) << 6; // Bit 6   = button 6
+	p2_btn  = ((in2  >>  7) & 0x0001);      // Bit 0   = start button
+	p2_btn |= ((in2  >>  4) & 0x0007) << 1; // Bit 1-3 = buttons 1-3
+	p2_btn |= ((in3h >>  8) & 0x0003) << 4; // Bit 4-5 = buttons 4-5
+	p2_btn |= ((in3h >> 11) & 0x0001) << 6; // Bit 6   = button 6
+	coin    = ((in1h >>  8) & 0x0003);      // Bit 0-1 = coin switches
+	coin   |= ((in1h >> 12) & 0x0001) << 2; // Bit 2   = service button
+	coin   |= ((in3l >> 10) & 0x0001) << 3; // Bit 3   = test button
+	coin   |= ((in1h >> 10) & 0x0003) << 4; // Bit 4-5 = PCMCIA cards
+
+	output->p1_joy = (in2 >> 8) & 0x000f;
+	output->p1_btn = p1_btn;
+	output->p2_joy = in2 & 0x000f;
+	output->p2_btn = p2_btn;
+	output->coin   = coin;
+	output->dip_sw = in1l & 0x000f;
+}
+
+/* I/O board (light control) utilities */
+
+// This function controls light outputs on analog I/O boards.
+void set_lights_analog(uint32_t lights) {
+	uint32_t bits;
+
+	bits  = (lights & 0x01010101) << 7; // Lamp n*8+0 -> bit n*8+7
+	bits |= (lights & 0x02020202) << 5; // Lamp n*8+1 -> bit n*8+6
+	bits |= (lights & 0x04040404) >> 1; // Lamp n*8+2 -> bit n*8+1
+	bits |= (lights & 0x08080808) >> 3; // Lamp n*8+3 -> bit n*8+0
+	bits |= (lights & 0x10101010) << 1; // Lamp n*8+4 -> bit n*8+5
+	bits |= (lights & 0x20202020) >> 1; // Lamp n*8+5 -> bit n*8+4
+	bits |= (lights & 0x40404040) >> 3; // Lamp n*8+6 -> bit n*8+3
+	bits |= (lights & 0x80808080) >> 5; // Lamp n*8+7 -> bit n*8+2
+
+	K573_IO_BOARD[ANALOG_IO_LIGHTS0] = (bits)       & 0xff;
+	K573_IO_BOARD[ANALOG_IO_LIGHTS1] = (bits >>  8) & 0xff;
+	K573_IO_BOARD[ANALOG_IO_LIGHTS2] = (bits >> 16) & 0xff;
+	K573_IO_BOARD[ANALOG_IO_LIGHTS3] = (bits >> 24) & 0xff;
+}
+
+// This function controls light outputs on digital I/O boards (i.e. the ones
+// that include MP3 playback hardware in addition to the light control).
+// TODO: test this on real hardware -- it might not work if lights are handled
+// by the board's FPGA, which requires a binary blob...
+void set_lights_digital(uint32_t lights) {
+	uint32_t bits;
+
+	bits  = (lights & 0x11111111);      // Lamp n*4+0 -> bit n*4+0
+	bits |= (lights & 0x22222222) << 1; // Lamp n*4+1 -> bit n*4+2
+	bits |= (lights & 0x44444444) << 1; // Lamp n*4+2 -> bit n*4+3
+	bits |= (lights & 0x88888888) >> 2; // Lamp n*4+3 -> bit n*4+1
+
+	K573_IO_BOARD[DIGITAL_IO_LIGHTS0] = ((bits)       & 0xf) << 12;
+	K573_IO_BOARD[DIGITAL_IO_LIGHTS1] = ((bits >>  4) & 0xf) << 12;
+	K573_IO_BOARD[DIGITAL_IO_LIGHTS2] = ((bits >>  8) & 0xf) << 12;
+	K573_IO_BOARD[DIGITAL_IO_LIGHTS3] = ((bits >> 12) & 0xf) << 12;
+	K573_IO_BOARD[DIGITAL_IO_LIGHTS4] = ((bits >> 16) & 0xf) << 12;
+	K573_IO_BOARD[DIGITAL_IO_LIGHTS5] = ((bits >> 20) & 0xf) << 12;
+	//K573_IO_BOARD[DIGITAL_IO_LIGHTS6] = ((bits >> 24) & 0xf) << 12;
+	K573_IO_BOARD[DIGITAL_IO_LIGHTS7] = ((bits >> 28) & 0xf) << 12;
+}
+
+/* Main */
+
+static CONTEXT ctx;
+
+#define SHOW_STATUS(...) { FntPrint(-1, __VA_ARGS__); FntFlush(-1); display(&ctx); }
+#define SHOW_ERROR(...)  { SHOW_STATUS(__VA_ARGS__); while (1) __asm__("nop"); }
+
+int main(int argc, const char* argv[]) {
+	// Reinitialize the heap and relocate the stack to allow the 573's full 4
+	// MB of RAM to be used. This isn't strictly required; executables designed
+	// for 2 MB of RAM will also run fine on the 573 (obviously).
+	// FIXME: this seems to be broken currently
+	//__asm__ volatile("li $sp, 0x803fffe0");
+	//_mem_init(0x400000, 0x20000);
+
+	EXP1_ADDR     = 0x1f000000;
+	EXP1_CTRL     = 0x24173f47; // 573 BIOS uses this value
+	K573_WATCHDOG = 0;
+
+	init_context(&ctx);
+
+	// Determine whether we are running on a 573 by fetching the version string
+	// from the BIOS.
+	const char *const version = (const char *const) GetSystemInfo(0x02);
+	//if (strncmp(version, "Konami OS", 9))
+		//SHOW_ERROR("ERROR: NOT RUNNING ON A SYSTEM 573!\n\n[%s]\n", version);
+
+	uint32_t counter       = 0;
+	uint8_t  last_joystick = 0xff;
+	uint8_t  last_buttons  = 0xff;
+	uint32_t current_light = 0;
+	uint32_t is_digital    = 0;
+
+	while (1) {
+		FntPrint(-1, "COUNTER=%d\n", counter++);
+
+		JAMMAInputs inputs;
+		get_jamma_inputs(&inputs);
+
+		FntPrint(-1, "\nJAMMA INPUTS:\n");
+		FntPrint(-1, " P1 JOYSTICK =%04@\n", inputs.p1_joy);
+		FntPrint(-1, " P1 BUTTONS  =%07@\n", inputs.p1_btn);
+		FntPrint(-1, " P2 JOYSTICK =%04@\n", inputs.p2_joy);
+		FntPrint(-1, " P2 BUTTONS  =%07@\n", inputs.p2_btn);
+		FntPrint(-1, " COIN/SERVICE=%04@\n", inputs.coin & 0xf);
+		FntPrint(-1, " DIP SWITCHES=%04@\n", inputs.dip_sw);
+
+		FntPrint(-1, "\nCABINET LIGHTS:\n");
+		FntPrint(-1, " BOARD=%s I/O\n", is_digital ? "DIGITAL" : "ANALOG");
+		FntPrint(-1, " LIGHT=%d\n\n",   current_light);
+		FntPrint(-1, " [START]      CHANGE BOARD TYPE\n");
+		FntPrint(-1, " [LEFT/RIGHT] SELECT LIGHT TO TEST\n");
+
+		// Request the current date/time from the RTC and display it.
+		K573_RTC[RTC_CTRL] |= 0x40;
+		FntPrint(-1, "\nRTC:\n");
+		FntPrint(
+			-1,
+			" %02d-%02d-%02d %02d:%02d:%02d\n",
+			btoi(K573_RTC[RTC_YEAR]),
+			btoi(K573_RTC[RTC_MONTH]),
+			btoi(K573_RTC[RTC_DAY_OF_MONTH] & 0x3f),
+			btoi(K573_RTC[RTC_HOURS]),
+			btoi(K573_RTC[RTC_MINUTES]),
+			btoi(K573_RTC[RTC_SECONDS] & 0x7f)
+		);
+
+		FntPrint(-1, "\nSYSTEM:\n");
+		FntPrint(-1, " KERNEL=%s\n",   version);
+		FntPrint(-1, " PCMCIA=%02@\n", inputs.coin >> 4);
+
+		FntFlush(-1);
+		display(&ctx);
+
+		// Reset the watchdog. This must be done at least once per frame to
+		// prevent the 573 from rebooting.
+		K573_WATCHDOG = 0;
+
+		if (is_digital)
+			set_lights_digital(1 << current_light);
+		else
+			set_lights_analog(1 << current_light);
+
+		// Handle inputs.
+		if ((last_joystick & 0x01) && !(inputs.p1_joy & 0x01)) // Left
+			current_light--;
+		if ((last_joystick & 0x02) && !(inputs.p1_joy & 0x02)) // Right
+			current_light++;
+		if ((last_buttons & 0x02) && !(inputs.p1_btn & 0x02)) // Button 1
+			current_light--;
+		if ((last_buttons & 0x04) && !(inputs.p1_btn & 0x04)) // Button 2
+			current_light++;
+		if ((last_buttons & 0x01) && !(inputs.p1_btn & 0x01)) { // Start
+			is_digital = !is_digital;
+			if (is_digital)
+				set_lights_analog(0);
+			else
+				set_lights_digital(0);
+		}
+
+		current_light %= 32;
+		last_joystick  = inputs.p1_joy;
+		last_buttons   = inputs.p1_btn;
+	}
+
+	return 0;
+}