diff --git a/fet.c b/fet.c
index dfc7913..10debe5 100644
--- a/fet.c
+++ b/fet.c
@@ -15,7 +15,7 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  *
- * Various constants and tables come from fet430uif, written by Robert
+ * Various constants and tables come from uif430, written by Robert
  * Kavaler (kavaler@diva.com). This is available under the same license
  * as this program, from www.relavak.com.
  */
@@ -36,7 +36,7 @@ static int fet_is_rf2500;
 /**********************************************************************
  * FET command codes.
  *
- * These come from fet430uif by Robert Kavaler (kavaler@diva.com).
+ * These come from uif430 by Robert Kavaler (kavaler@diva.com).
  * www.relavak.com
  */
 
@@ -194,7 +194,7 @@ static struct {
 #define PTYPE_NAK		5
 #define PTYPE_FLASH_ACK		6
 
-/* This table is taken from fet430uif */
+/* This table is taken from uif430 */
 static const char *error_strings[] =
 {
         "No error",                                                     // 0
@@ -489,7 +489,7 @@ static int xfer(int command_code, const char *data, int datalen,
 
 static int fet_version;
 
-/* Reply data taken from fet430uif */
+/* Reply data taken from uif430 */
 #define ID_REPLY_LEN	18
 
 static const struct {
diff --git a/main.c b/main.c
index 510f7c8..a264d9b 100644
--- a/main.c
+++ b/main.c
@@ -597,11 +597,14 @@ static void reader_loop(void)
 
 static void usage(const char *progname)
 {
-	fprintf(stderr, "Usage: %s [-u device] [command ...]\n"
+	fprintf(stderr, "Usage: %s [-u device] [-j] [command ...]\n"
 "\n"
-"By default, the first RF2500 device on the USB bus is opened. If -u is\n"
-"given, then a UIF device attached to the specified serial port is\n"
-"opened.\n"
+"    -u device\n"
+"        Open the given tty device (MSP430 UIF compatible devices).\n"
+"    -j\n"
+"        Use JTAG, rather than spy-bi-wire (UIF devices only).\n"
+"\n"
+"By default, the first RF2500 device on the USB bus is opened.\n"
 "\n"
 "If commands are given, they will be executed. Otherwise, an interactive\n"
 "command reader is started.\n",
@@ -613,6 +616,7 @@ int main(int argc, char **argv)
 	const char *uif_device = NULL;
 	int opt;
 	int result;
+	int want_jtag = 0;
 
 	puts(
 "MSPDebug version 0.2 - debugging tool for the eZ430\n"
@@ -620,12 +624,16 @@ int main(int argc, char **argv)
 "This is free software; see the source for copying conditions.  There is NO\n"
 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n");
 
-	while ((opt = getopt(argc, argv, "u:")) >= 0)
+	while ((opt = getopt(argc, argv, "u:j")) >= 0)
 		switch (opt) {
 		case 'u':
 			uif_device = optarg;
 			break;
 
+		case 'j':
+			want_jtag = 1;
+			break;
+
 		default:
 			usage(argv[0]);
 			return -1;
@@ -633,7 +641,7 @@ int main(int argc, char **argv)
 
 	/* Open the appropriate device */
 	if (uif_device)
-		result = uif_open(uif_device);
+		result = uif_open(uif_device, want_jtag);
 	else
 		result = rf2500_open();
 
diff --git a/uif.c b/uif.c
index 73186b6..f52ee44 100644
--- a/uif.c
+++ b/uif.c
@@ -94,7 +94,7 @@ static const struct fet_transport serial_transport = {
 	.close = serial_close
 };
 
-int uif_open(const char *device)
+int uif_open(const char *device, int want_jtag)
 {
 	struct termios attr;
 
@@ -116,7 +116,8 @@ int uif_open(const char *device)
 		return -1;
 	}
 
-	if (fet_open(&serial_transport, FET_PROTO_SPYBIWIRE, 3000) < 0) {
+	if (fet_open(&serial_transport, want_jtag ? 0 : FET_PROTO_SPYBIWIRE,
+			3000) < 0) {
 		close(serial_fd);
 		return -1;
 	}
diff --git a/uif.h b/uif.h
index e143b4b..28d6963 100644
--- a/uif.h
+++ b/uif.h
@@ -23,6 +23,6 @@
  * a kernel-supported serial interface. The argument given should be the
  * filename of the relevant tty device.
  */
-int uif_open(const char *device);
+int uif_open(const char *device, int want_jtag);
 
 #endif