diff --git a/atusb/fw/atspi/atspi.c b/atusb/fw/atspi/atspi.c
index cee1732..7ca229b 100644
--- a/atusb/fw/atspi/atspi.c
+++ b/atusb/fw/atspi/atspi.c
@@ -18,10 +18,31 @@
 #include "version.h"
 
 
+static int in_test_mode = 0;
+
+
+static void set_test_mode(int on)
+{
+	in_test_mode = on;
+	if (on) {
+		TST_MODE |= 1 << TST_BIT;
+		TST = 1;
+		LED_MODE |= 1 << LED_BIT;
+	} else {
+		TST = 0;
+		TST_MODE &= ~(1 << TST_BIT);
+		LED_MODE &= ~(1 << LED_BIT);
+		LED = 0;
+	}
+}
+
+
 void reset_rf(void)
 {
 	int i;
 
+	set_test_mode(0);
+
 	nRST_RF = 0;
 	/*
 	 * 11.4.12: min 625 ns.
@@ -32,6 +53,12 @@ void reset_rf(void)
 }
 
 
+void test_mode(void)
+{
+	set_test_mode(1);
+}
+
+
 static void init_io(void)
 {
 	/*
@@ -44,6 +71,7 @@ static void init_io(void)
 	 * nRST_RF	push-pull	1
 	 * IRQ_RF	open drain	1	(input)
 	 * SLP_TR	push-pull	0
+	 * TST		open drain 	0
 	 *
 	 * LED		push-pull	0	(set up by boot loader)
 	 *
@@ -63,7 +91,7 @@ static void init_io(void)
 	SLP_TR = 0;
 	SLP_TR_MODE |= 1 << SLP_TR_BIT;
 
-	P0 = 1;	/* IRQ_RF = 1; LED = 0; the rest is unused */
+	P0 = 1;	/* IRQ_RF = 1; LED = 0; TST = Z; the rest is unused */
 	P3 = 0;
 
 #if 0
@@ -104,6 +132,10 @@ void main(void)
 	ep0_init();
 
 	while (1) {
+		if (in_test_mode) {
+			i++;
+			LED = !(i >> 13);
+		}
 		usb_poll();
 	}
 }
diff --git a/atusb/fw/atspi/ep0.c b/atusb/fw/atspi/ep0.c
index e2e4ecc..643dead 100644
--- a/atusb/fw/atspi/ep0.c
+++ b/atusb/fw/atspi/ep0.c
@@ -26,6 +26,7 @@
 
 
 extern void reset_rf(void);
+extern void test_mode(void);
 
 
 #define debug(...)
@@ -151,6 +152,11 @@ static __bit my_setup(struct setup_request *setup) __reentrant
 		usb_send(&ep0, buf, 1, NULL, NULL);
 		return 1;
 
+	case ATSPI_TO_DEV(ATSPI_TEST):
+		debug("ATSPI_TEST\n");
+		test_mode();
+		return 1;
+
 	case ATSPI_TO_DEV(ATSPI_REG_WRITE):
 		debug("ATSPI_REG_WRITE\n");
 		nSS = 0;
diff --git a/atusb/fw/common/io.h b/atusb/fw/common/io.h
index 7ab8930..eac4355 100644
--- a/atusb/fw/common/io.h
+++ b/atusb/fw/common/io.h
@@ -30,5 +30,6 @@
 #define	nRST_RF	P2_0
 #define	IRQ_RF	P0_0
 #define	SLP_TR	P2_1
+#define	TST	P0_7
 
 #endif /* !IO_H */
diff --git a/atusb/fw/include/at86rf230.h b/atusb/fw/include/at86rf230.h
index 20a3aa3..fb66b96 100644
--- a/atusb/fw/include/at86rf230.h
+++ b/atusb/fw/include/at86rf230.h
@@ -67,6 +67,9 @@ enum {
 	REG_XAH_CTRL		= 0x2c,
 	REG_CSMA_SEED_0		= 0x2d,
 	REG_CSMA_SEED_1		= 0x2e,
+
+	REG_CONT_TX_0		= 0x36,
+	REG_CONT_TX_1		= 0x3d,
 };
 
 /* --- TRX_STATUS [7] ------------------------------------------------------ */
@@ -113,7 +116,7 @@ enum {
 	TRAC_STATUS_INVALID			= 7
 };
 
-/* --- TRX_CMD [4:0] ----------------------------------------------------- */
+/* --- TRX_STATE [4:0] ----------------------------------------------------- */
 
 #define	TRX_CMD_SHIFT	0
 #define	TRX_CMD_MASK	7
@@ -285,4 +288,15 @@ enum {
 #define CSMA_SEED_1_SHIFT	0
 #define	CSMA_SEED_1_MASK	7
 
+/* --- REG_CONT_TX_0 [7:0] ------------------------------------------------- */
+
+#define	CONT_TX_MAGIC		0x0f
+
+/* --- REG_CONT_TX_1 [7:0] ------------------------------------------------- */
+
+#define	CONT_TX_MOD		0x00	/* modulated */
+#define	CONT_TX_M2M		0x10	/* f_CH-2 MHz */
+#define	CONT_TX_M500K		0x80	/* f_CH-0.5 MHz */
+#define	CONT_TX_P500K		0xc0	/* f_CH+0.5 MHz */
+
 #endif /* !AT86RF230_H */
diff --git a/atusb/fw/include/atspi/ep0.h b/atusb/fw/include/atspi/ep0.h
index 4dc3928..bc128ba 100644
--- a/atusb/fw/include/atspi/ep0.h
+++ b/atusb/fw/include/atspi/ep0.h
@@ -23,6 +23,7 @@
  *
  * host->	ATSPI_RF_RESET		-		-	0
  * ->host	ATSPI_POLL_INT		-		-	1
+ * host->	ATSPI_TEST		-		-	0
  *
  * host->	ATSPI_REG_WRITE		value		addr	0
  * ->host	ATSPI_REG_READ		-		addr	1
@@ -36,10 +37,11 @@
  * EP0 protocol:
  *
  * 0.0	initial release
+ * 0.1  addition of ATSPI_TEST
  */
 
 #define EP0ATSPI_MAJOR	0	/* EP0 protocol, major revision */
-#define EP0ATSPI_MINOR	0	/* EP0 protocol, minor revision */
+#define EP0ATSPI_MINOR	1	/* EP0 protocol, minor revision */
 
 #define	HW_TYPE_100813	0	/* 100813 */
 
@@ -65,6 +67,7 @@ enum atspi_requests {
 	ATSPI_RESET,
 	ATSPI_RF_RESET			= 0x10,
 	ATSPI_POLL_INT,
+	ATSPI_TEST,
 	ATSPI_REG_WRITE			= 0x20,
 	ATSPI_REG_READ,
 	ATSPI_BUF_WRITE,