diff --git a/libs/openzap/src/dsp/uart.c b/libs/openzap/src/dsp/uart.c
index cbd81b2236..c6e2105fcc 100644
--- a/libs/openzap/src/dsp/uart.c
+++ b/libs/openzap/src/dsp/uart.c
@@ -46,8 +46,7 @@
  *	attributes structure is used.
 */
 
-void
-dsp_uart_attr_init (dsp_uart_attr_t *attr)
+void dsp_uart_attr_init (dsp_uart_attr_t *attr)
 {
 	memset (attr, 0, sizeof (*attr));
 }
@@ -61,22 +60,19 @@ dsp_uart_attr_init (dsp_uart_attr_t *attr)
  *	zero == ok, -1 == fail.
 */
 
-void (*
-dsp_uart_attr_get_bytehandler (dsp_uart_attr_t *attr, void **bytehandler_arg)) (void *, int)
+bytehandler_func_t dsp_uart_attr_get_bytehandler (dsp_uart_attr_t *attr, void **bytehandler_arg)
 {
 	*bytehandler_arg = attr -> bytehandler_arg;
 	return (attr -> bytehandler);
 }
 
-void
-dsp_uart_attr_set_bytehandler (dsp_uart_attr_t *attr, void (*bytehandler) (void *, int ), void *bytehandler_arg)
+void dsp_uart_attr_set_bytehandler (dsp_uart_attr_t *attr, bytehandler_func_t bytehandler, void *bytehandler_arg)
 {
 	attr -> bytehandler = bytehandler;
 	attr -> bytehandler_arg = bytehandler_arg;
 }
 
-dsp_uart_handle_t *
-dsp_uart_create (dsp_uart_attr_t *attr)
+dsp_uart_handle_t *dsp_uart_create (dsp_uart_attr_t *attr)
 {
 	dsp_uart_handle_t	*handle;
 
@@ -86,21 +82,28 @@ dsp_uart_create (dsp_uart_attr_t *attr)
 	}
 	memset (handle, 0, sizeof (handle));
 
-	// fill the attributes member
+	/* fill the attributes member */
 	memcpy (&handle -> attr, attr, sizeof (*attr));
 
 	return (handle);
 }
 
-void
-dsp_uart_bit_handler (void *x, int bit)
+void dsp_uart_destroy (dsp_uart_handle_t **handle)
+{
+	if (*handle) {
+		free(*handle);
+		*handle = NULL;
+	}
+}
+
+
+void dsp_uart_bit_handler (void *x, int bit)
 {
 	dsp_uart_handle_t *handle = (dsp_uart_handle_t *) x;
 
-//	printf ("bit %d handle -> have_start %d handle -> data %02X handle -> nbits %d\n", bit, handle -> have_start, handle -> data, handle -> nbits);
 	if (!handle -> have_start) {
 		if (bit) {
-			return;		// waiting for start bit (0)
+			return;		/* waiting for start bit (0) */
 		}
 		handle -> have_start = 1;
 		handle -> data = 0;
@@ -118,11 +121,11 @@ dsp_uart_bit_handler (void *x, int bit)
 		handle -> data = 0;
 		handle -> have_start = 0;
 
-// might consider handling errors in the future...
+/* might consider handling errors in the future... */
 #if 0
 	} else if (handle -> nbits > 8) {
 		if (!bit) {
-			// framing error; expected stop bit (mark, 1)
+			/* framing error; expected stop bit (mark, 1) */
 			printf ("FRAME"); fflush (stdout);
 		} else {
 			handle -> have_start = 0;
diff --git a/libs/openzap/src/dsp/uart.h b/libs/openzap/src/dsp/uart.h
index 7c3a9164b0..9989ab935d 100644
--- a/libs/openzap/src/dsp/uart.h
+++ b/libs/openzap/src/dsp/uart.h
@@ -35,18 +35,20 @@
 #ifndef	__UART_H__
 #define	__UART_H__
 
+typedef void (*bytehandler_func_t) (void *, int);
+
 typedef struct dsp_uart_attr_s
 {
-	void				(*bytehandler) (void *, int);	// byte handler
-	void				*bytehandler_arg;				// arbitrary ID passed to bytehandler as first argument
+	bytehandler_func_t	bytehandler;					/* byte handler */
+	void				*bytehandler_arg;				/* arbitrary ID passed to bytehandler as first argument */
 }	dsp_uart_attr_t;
 
 typedef struct
 {
 	dsp_uart_attr_t		attr;
-	int					have_start;						// wait for start bit to show up
-	int					data;							// data buffer
-	int					nbits;							// number of bits accumulated so far
+	int					have_start;						/* wait for start bit to show up */
+	int					data;							/* data buffer */
+	int					nbits;							/* number of bits accumulated so far */
 }	dsp_uart_handle_t;
 
 /*
@@ -56,24 +58,18 @@ typedef struct
  *		a) create the attributes structure (dsp_uart_attr_init)
  *		b) initialize fields in the attributes structure (dsp_uart_attr_set_*)
  *		c) create a Bell-202 handle (dsp_uart_create)
- *		d) feed samples through the handler (dsp_uart_sample)
+ *		d) feed bits through dsp_uart_bit_handler
 */
 
-extern	void					dsp_uart_attr_init (dsp_uart_attr_t *attributes);
+void					dsp_uart_attr_init (dsp_uart_attr_t *attributes);
 
-extern  void					(*dsp_uart_attr_get_bithandler (dsp_uart_attr_t *attributes, void **bithandler_arg)) (void *, int);
-extern	void					dsp_uart_attr_set_bithandler (dsp_uart_attr_t *attributes, void (*bithandler) (void *, int ), void *bithandler_arg);
-extern  void					(*dsp_uart_attr_get_bytehandler (dsp_uart_attr_t *attributes, void **bytehandler_arg)) (void *, int);
-extern	void					dsp_uart_attr_set_bytehandler (dsp_uart_attr_t *attributes, void (*bytehandler) (void *, int ), void *bytehandler_arg);
-extern	int						dsp_uart_attr_get_samplerate (dsp_uart_attr_t *attributes);
-extern	int						dsp_uart_attr_set_samplerate (dsp_uart_attr_t *attributes, int samplerate);
+bytehandler_func_t		dsp_uart_attr_get_bytehandler (dsp_uart_attr_t *attributes, void **bytehandler_arg);
+void					dsp_uart_attr_set_bytehandler (dsp_uart_attr_t *attributes, bytehandler_func_t bytehandler, void *bytehandler_arg);
 
-extern	dsp_uart_handle_t *		dsp_uart_create (dsp_uart_attr_t *attributes);
-extern	void					dsp_uart_destroy (dsp_uart_handle_t *handle);
+dsp_uart_handle_t *		dsp_uart_create (dsp_uart_attr_t *attributes);
+void					dsp_uart_destroy (dsp_uart_handle_t **handle);
 
-extern	void					dsp_uart_sample (dsp_uart_handle_t *handle, double normalized_sample);
-
-extern	void					dsp_uart_bit_handler (void *handle, int bit);
+void					dsp_uart_bit_handler (void *handle, int bit);
 
 #endif	// __UART_H__