add a new pc speaker driver and a multiboot header

2 files changed, 22 insertions, 0 deletions

diff --git a/drivers/include/pcspkr.h b/drivers/include/pcspkr.h
new file mode 100644
index 0000000..84e640f
--- /dev/null
+++ b/drivers/include/pcspkr.h
@@ -0,0 +1,3 @@
+#include <stdint.h>
+
+void pcspkr_play(uint32_t freq);
diff --git a/drivers/pcspkr.c b/drivers/pcspkr.c
new file mode 100644
index 0000000..33c0540
--- /dev/null
+++ b/drivers/pcspkr.c
@@ -0,0 +1,19 @@
+#include <stdint.h>
+#include "io.h"
+#include "pcspkr.h"
+
+void pcspkr_play(uint32_t freq)
+{
+    uint32_t div;
+    uint8_t tmp;
+
+    div = 1193180 / freq;
+    outb(0x43, 0xb6);
+    outb(0x42, (uint8_t)(div));
+    outb(0x42, (uint8_t)(div >> 8));
+
+    tmp = inb(0x61);
+    if (tmp != (tmp | 3)) {
+        outb(0x61, tmp | 3);
+    }
+}