pcspkr module because why not

modules/pcspkr.c

@@ -0,0 +1,71 @@
+#include <module.h>
+#include <printf.h>
+#include <mod/shell.h>
+
+static void note(int length, int freq) {
+
+	uint32_t div = 11931800 / freq;
+	uint8_t  t;
+
+	outportb(0x43, 0xb6);
+	outportb(0x42, (uint8_t)(div));
+	outportb(0x42, (uint8_t)(div >> 8));
+
+	t = inportb(0x61);
+	outportb(0x61, t | 0x3);
+
+	unsigned long s, ss;
+	relative_time(0, length, &s, &ss);
+	sleep_until((process_t *)current_process, s, ss);
+	switch_task(0);
+
+	t = inportb(0x61) & 0xFC;
+	outportb(0x61, t);
+
+}
+
+DEFINE_SHELL_FUNCTION(beep, "Beep.") {
+	fprintf(tty, "beep\n");
+
+	note(20, 15680);
+	note(10, 11747);
+	note(10, 12445);
+	note(20, 13969);
+	note(10, 12445);
+	note(10, 11747);
+	note(20, 10465);
+	note(10, 10465);
+	note(10, 12445);
+	note(20, 15680);
+	note(10, 13969);
+	note(10, 12445);
+	note(30, 11747);
+	note(10, 12445);
+	note(20, 13969);
+	note(20, 15680);
+	note(20, 12445);
+	note(20, 10465);
+	note(20, 10465);
+#if 0
+		note(10, 1000);
+		note(10, 800);
+		note(10, 600);
+		note(10, 400);
+		note(10, 200);
+	}
+#endif
+
+	return 0;
+}
+
+static int init(void) {
+	BIND_SHELL_FUNCTION(beep);
+	return 0;
+}
+
+static int fini(void) {
+	return 0;
+}
+
+MODULE_DEF(crash, init, fini);
+MODULE_DEPENDS(debugshell);