From 15ac1a8086971cb500bd09dd97bf62e111c2be90 Mon Sep 17 00:00:00 2001
From: "B. Watson" <yalhcru@gmail.com>
Date: Tue, 13 Sep 2016 04:49:13 -0400
Subject: pokey emulation, plus more labels

---
 pokeytest/playsnd.c | 114 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 114 insertions(+)
 create mode 100644 pokeytest/playsnd.c

(limited to 'pokeytest/playsnd.c')

diff --git a/pokeytest/playsnd.c b/pokeytest/playsnd.c
new file mode 100644
index 0000000..0f76879
--- /dev/null
+++ b/pokeytest/playsnd.c
@@ -0,0 +1,114 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "pokey.h"
+
+#define ROM_FILE "../jumpmanjr.rom"
+#define ROM_SIZE 0x4000
+
+#define PAL_BUF_SIZE 882
+#define NTSC_BUF_SIZE 735
+
+unsigned char sndbuf[PAL_BUF_SIZE + 1];
+
+unsigned char rom[ROM_SIZE];
+
+void usage(void) {
+	fprintf(stderr, "usage: playsnd [-p] 0xaddr\n");
+	exit(1);
+}
+
+void load_rom(void) {
+	int size;
+	FILE *f;
+
+	f = fopen(ROM_FILE, "rb");
+	if(!f) {
+		perror(ROM_FILE);
+		usage();
+	}
+
+	size = fread(rom, 1, ROM_SIZE, f);
+	if(size != ROM_SIZE) {
+		fprintf(stderr, "file %s should be %d bytes long, not %d\n",
+				ROM_FILE, ROM_SIZE, size);
+		usage();
+	}
+
+	fprintf(stderr, "loaded ROM %s, %d bytes\n", ROM_FILE, size);
+}
+
+void play_frames(unsigned char count, int buf_size) {
+	fprintf(stderr, "playing for %d frames\n", count);
+	while(count--) {
+		Pokey_process(sndbuf, buf_size);
+		fwrite(sndbuf, buf_size, 1, stdout);
+	}
+}
+
+void play_sfx(int addr, int buf_size) {
+	unsigned char *p = rom + (addr - 0x8000);
+
+	while(1) {
+		fprintf(stderr, "$%04lx: $%02x\n", (p - rom + 0x8000), *p);
+		switch(*p) {
+			case 0:
+				fprintf(stderr, "opcode 0 (snd_end)\n");
+				return;
+			case 1:
+				fprintf(stderr, "opcode 1 (snd_audc)\n");
+				Update_pokey_sound(audc1, *++p);
+				play_frames(*++p, buf_size);
+				++p;
+				break;
+			case 2:
+				fprintf(stderr, "opcode 2 (snd_jump)\n");
+				addr = *++p;
+				addr |= ( (*++p) << 8);
+				addr -= 0x8000;
+				p = rom + addr;
+				break;
+			case 3:
+				fprintf(stderr, "opcode 3 (snd_rest)\n");
+				Update_pokey_sound(audc1, 0);
+				play_frames(*++p, buf_size);
+				++p;
+				break;
+			default:
+				fprintf(stderr, "opcode $%02x (snd_note)\n", *p);
+				Update_pokey_sound(audf1, *p);
+				play_frames(*++p, buf_size);
+				++p;
+				break;
+		}
+	}
+}
+
+int main(int argc, char **argv) {
+	int buf_size = NTSC_BUF_SIZE;
+	int addr;
+
+	if(argc < 2 || argc > 3) usage();
+
+	if(argc == 3) {
+		buf_size = PAL_BUF_SIZE;
+		addr = (int)strtol(argv[2], 0, 0);
+	} else {
+		addr = (int)strtol(argv[1], 0, 0);
+	}
+
+	if(addr < 0x8000 || addr > 0xbfff) {
+		fprintf(stderr, "invalid address, must be 0x8fff thru 0xbfff\n");
+		usage();
+	}
+
+	load_rom();
+
+	fprintf(stderr, "playing sfx at $%04x, buf_size %d\n", addr, buf_size);
+
+	Pokey_sound_init(FREQ_17_APPROX, 44100);
+	play_sfx(addr, buf_size);
+
+	return(0);
+}
+
-- 
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