diff --git a/firmware/src/boards/cynthion_d11/fpga.c b/firmware/src/boards/cynthion_d11/fpga.c
index ce5f944..7c2dbab 100644
--- a/firmware/src/boards/cynthion_d11/fpga.c
+++ b/firmware/src/boards/cynthion_d11/fpga.c
@@ -10,6 +10,7 @@
 
 #include "apollo_board.h"
 #include "jtag.h"
+#include "fpga.h"
 
 
 /*
@@ -68,4 +69,7 @@ void trigger_fpga_reconfiguration(void)
 
 	gpio_set_pin_level(FPGA_PROGRAM, true);
 	gpio_set_pin_direction(FPGA_PROGRAM, GPIO_DIRECTION_IN);
+
+	// Update internal state.
+	fpga_online = true;
 }
diff --git a/firmware/src/boards/cynthion_d11/fpga_adv.c b/firmware/src/boards/cynthion_d11/fpga_adv.c
index 329d5d0..9588d2f 100644
--- a/firmware/src/boards/cynthion_d11/fpga_adv.c
+++ b/firmware/src/boards/cynthion_d11/fpga_adv.c
@@ -7,6 +7,7 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
+#include <stdbool.h>
 #include "fpga_adv.h"
 #include "usb_switch.h"
 #include "apollo_board.h"
@@ -23,6 +24,9 @@
 #define TIMEOUT 100UL
 static uint32_t last_phy_adv = 0;
 
+// Allow deferred switching of the USB port.
+static bool defer_hand_off = false;
+
 // Create a reference to our SERCOM object.
 typedef Sercom sercom_t;
 static sercom_t *sercom = SERCOM1;
@@ -107,9 +111,12 @@ void fpga_adv_init(void)
 void fpga_adv_task(void)
 {
 #ifdef BOARD_HAS_USB_SWITCH
-        // Take over USB after timeout
-	if (board_millis() - last_phy_adv >= TIMEOUT) {
+    // Take over USB after timeout
+	if (fpga_requesting_port() == false) {
 		take_over_usb();
+	} else if (defer_hand_off) {
+		hand_off_usb();
+		defer_hand_off = false;
 	}
 #endif
 }
@@ -120,12 +127,26 @@ void fpga_adv_task(void)
 void honor_fpga_adv(void)
 {
 #ifdef BOARD_HAS_USB_SWITCH
-	if (board_millis() - last_phy_adv < TIMEOUT) {
+	if (fpga_requesting_port()) {
 		hand_off_usb();
+	} else {
+		defer_hand_off = true;
 	}
 #endif
 }
 
+/**
+ * True if we received an advertisement message within the last time window.
+ */
+bool fpga_requesting_port(void)
+{
+#ifdef BOARD_HAS_USB_SWITCH
+	return board_millis() - last_phy_adv < TIMEOUT;
+#else
+	return false;
+#endif
+}
+
 
 #ifdef BOARD_HAS_USB_SWITCH
 /**
diff --git a/firmware/src/boards/cynthion_d11/led.c b/firmware/src/boards/cynthion_d11/led.c
index a8e4fac..01aa054 100644
--- a/firmware/src/boards/cynthion_d11/led.c
+++ b/firmware/src/boards/cynthion_d11/led.c
@@ -19,10 +19,13 @@
 
 
 #include "led.h"
+#include "fpga.h"
+#include "fpga_adv.h"
+#include "usb_switch.h"
 
 
 /** Store the current LED blink pattern. */
-static blink_pattern_t blink_pattern = BLINK_IDLE;
+static led_pattern_t led_pattern = LED_IDLE;
 
 
 /**
@@ -116,16 +119,16 @@ static void display_led_number(uint8_t number)
 
 
 /**
- * Sets the active LED blink pattern.
+ * Sets the active LED pattern.
  */
-void led_set_blink_pattern(blink_pattern_t pattern)
+void led_set_pattern(led_pattern_t pattern)
 {
-    blink_pattern = pattern;
+    led_pattern = pattern;
     leds_off();
     // Values of 0 to 31 should be set immediately as static patterns.
-    if (blink_pattern < 32) {
+    if (led_pattern < 32) {
       for (int i = 0; i < 5; i++) {
-        if (blink_pattern & (1 << i)) {
+        if (led_pattern & (1 << i)) {
           display_led_number(i);
         }
       }
@@ -134,36 +137,45 @@ void led_set_blink_pattern(blink_pattern_t pattern)
 
 
 /**
- * Task that handles blinking the heartbeat LED.
+ * Task that handles LED updates.
  */
-void heartbeat_task(void)
+void led_task(void)
 {
   static uint32_t start_ms = 0;
   static uint8_t active_led = 0;
   static bool count_up = true;
 
   // Values of 0 to 31 define static patterns only.
-  if (blink_pattern < 32) {
+  if (led_pattern < 32) {
     return;
   }
 
-  // Blink every interval ms
-  if ( board_millis() - start_ms < blink_pattern) return; // not enough time
-  start_ms += blink_pattern;
+  // When the device is idle, use the following scheme for LEDs:
+  // - LED A: power indication (always on in Apollo)
+  // - LED B: FPGA allowed online (indicates PROGRAM toggle)
+  // - LED C: FPGA has requested CONTROL port
+  // - LED D: USB switched to FPGA
+  // - LED E: flashing patterns (e.g. fault indication)
+  if (led_pattern == LED_IDLE) {
+    led_set(LED_A, true);
+    led_set(LED_B, fpga_is_online());
+    led_set(LED_C, fpga_requesting_port());
+    led_set(LED_D, fpga_controls_usb_port());
+    led_set(LED_E, false);
+    return;
+  }
 
-  switch (blink_pattern) {
+  // Blink every interval ms
+  if ( board_millis() - start_ms < led_pattern) return; // not enough time
+  start_ms += led_pattern;
 
-    // Standard blink pattern for when the device is idle.
-    // Indicates that the device's JTAG lines are un-pulled.
-    case BLINK_IDLE:
-      led_toggle(LED_E);
-      break;
+  switch (led_pattern) {
 
     // Blink patterns for when the device is being used for JTAG
     // operation. When these are on, the uC is driving the JTAG lines,
     // so the JTAG header probably shouldn't used to drive the lines.
-    case BLINK_JTAG_CONNECTED:
-    case BLINK_JTAG_UPLOADING:
+    case LED_JTAG_CONNECTED:
+    case LED_JTAG_UPLOADING:
 
       // Sweep back and forth.
       if (active_led == 0xFF) {
@@ -182,7 +194,7 @@ void heartbeat_task(void)
 
     // Blink patterns for when the device is being used for SPI flash access.
     // When these are displayed,
-    case BLINK_FLASH_CONNECTED:
+    case LED_FLASH_CONNECTED:
 
       if (active_led == 5) {
         active_led = 0;
diff --git a/firmware/src/boards/cynthion_d21/fpga.c b/firmware/src/boards/cynthion_d21/fpga.c
index 17a1151..929345a 100644
--- a/firmware/src/boards/cynthion_d21/fpga.c
+++ b/firmware/src/boards/cynthion_d21/fpga.c
@@ -9,6 +9,7 @@
 #include <hal/include/hal_gpio.h>
 
 #include "jtag.h"
+#include "fpga.h"
 
 // List of pins used for FPGA interfacing.
 enum {
@@ -73,4 +74,7 @@ void trigger_fpga_reconfiguration(void)
 
 	gpio_set_pin_level(PIN_PROG, true);
 	gpio_set_pin_direction(PIN_PROG, GPIO_DIRECTION_IN);
+
+	// Update internal state.
+	fpga_online = true;
 }
diff --git a/firmware/src/boards/cynthion_d21/fpga_adv.c b/firmware/src/boards/cynthion_d21/fpga_adv.c
index b2c85f9..5a62561 100644
--- a/firmware/src/boards/cynthion_d21/fpga_adv.c
+++ b/firmware/src/boards/cynthion_d21/fpga_adv.c
@@ -6,6 +6,7 @@
  * Copyright (c) 2023 Great Scott Gadgets <info@greatscottgadgets.com>
  * SPDX-License-Identifier: BSD-3-Clause
  */
+#include <stdbool.h>
 
 /**
  * Initialize FPGA_ADV receive-only serial port
@@ -27,3 +28,11 @@ void fpga_adv_task(void)
 void honor_fpga_adv(void)
 {
 }
+
+/**
+ * True if we received an advertisement message within the last time window.
+ */
+bool fpga_requesting_port(void)
+{
+    return false;
+}
diff --git a/firmware/src/boards/cynthion_d21/led.c b/firmware/src/boards/cynthion_d21/led.c
index 05470c3..3625281 100644
--- a/firmware/src/boards/cynthion_d21/led.c
+++ b/firmware/src/boards/cynthion_d21/led.c
@@ -22,7 +22,7 @@
 
 
 /** Store the current LED blink pattern. */
-static blink_pattern_t blink_pattern = BLINK_IDLE;
+static led_pattern_t led_pattern = LED_IDLE;
 
 
 /**
@@ -103,16 +103,16 @@ static void display_led_number(uint8_t number)
 
 
 /**
- * Sets the active LED blink pattern.
+ * Sets the active LED pattern.
  */
-void led_set_blink_pattern(blink_pattern_t pattern)
+void led_set_pattern(led_pattern_t pattern)
 {
-    blink_pattern = pattern;
+    led_pattern = pattern;
     leds_off();
     // Values of 0 to 31 should be set immediately as static patterns.
-    if (blink_pattern < 32) {
+    if (led_pattern < 32) {
       for (int i = 0; i < 5; i++) {
-        if (blink_pattern & (1 << i)) {
+        if (led_pattern & (1 << i)) {
           display_led_number(i);
         }
       }
@@ -121,36 +121,36 @@ void led_set_blink_pattern(blink_pattern_t pattern)
 
 
 /**
- * Task that handles blinking the heartbeat LED.
+ * Task that handles LED updates.
  */
-void heartbeat_task(void)
+void led_task(void)
 {
   static uint32_t start_ms = 0;
   static uint8_t active_led = 0;
   static bool count_up = true;
 
   // Values of 0 to 31 define static patterns only.
-  if (blink_pattern < 32) {
+  if (led_pattern < 32) {
     return;
   }
 
   // Blink every interval ms
-  if ( board_millis() - start_ms < blink_pattern) return; // not enough time
-  start_ms += blink_pattern;
+  if ( board_millis() - start_ms < led_pattern) return; // not enough time
+  start_ms += led_pattern;
 
-  switch (blink_pattern) {
+  switch (led_pattern) {
 
     // Standard blink pattern for when the device is idle.
     // Indicates that the device's JTAG lines are un-pulled.
-    case BLINK_IDLE:
+    case LED_IDLE:
       led_toggle(LED_E);
       break;
 
     // Blink patterns for when the device is being used for JTAG
     // operation. When these are on, the uC is driving the JTAG lines,
     // so the JTAG header probably shouldn't used to drive the lines.
-    case BLINK_JTAG_CONNECTED:
-    case BLINK_JTAG_UPLOADING:
+    case LED_JTAG_CONNECTED:
+    case LED_JTAG_UPLOADING:
 
       // Sweep back and forth.
       if (active_led == 0xFF) {
@@ -169,7 +169,7 @@ void heartbeat_task(void)
 
     // Blink patterns for when the device is being used for SPI flash access.
     // When these are displayed,
-    case BLINK_FLASH_CONNECTED:
+    case LED_FLASH_CONNECTED:
 
       if (active_led == 5) {
         active_led = 0;
diff --git a/firmware/src/boards/daisho/fpga_adv.c b/firmware/src/boards/daisho/fpga_adv.c
index b2c85f9..5a62561 100644
--- a/firmware/src/boards/daisho/fpga_adv.c
+++ b/firmware/src/boards/daisho/fpga_adv.c
@@ -6,6 +6,7 @@
  * Copyright (c) 2023 Great Scott Gadgets <info@greatscottgadgets.com>
  * SPDX-License-Identifier: BSD-3-Clause
  */
+#include <stdbool.h>
 
 /**
  * Initialize FPGA_ADV receive-only serial port
@@ -27,3 +28,11 @@ void fpga_adv_task(void)
 void honor_fpga_adv(void)
 {
 }
+
+/**
+ * True if we received an advertisement message within the last time window.
+ */
+bool fpga_requesting_port(void)
+{
+    return false;
+}
diff --git a/firmware/src/boards/daisho/led.c b/firmware/src/boards/daisho/led.c
index 0ce2bc8..a6d30ac 100644
--- a/firmware/src/boards/daisho/led.c
+++ b/firmware/src/boards/daisho/led.c
@@ -21,15 +21,15 @@
 
 
 /** Store the current LED blink pattern. */
-static blink_pattern_t blink_pattern = BLINK_IDLE;
+static led_pattern_t led_pattern = LED_IDLE;
 
 
 /**
- * Sets the active LED blink pattern.
+ * Sets the active LED pattern.
  */
-void led_set_blink_pattern(blink_pattern_t pattern)
+void led_set_pattern(led_pattern_t pattern)
 {
-	blink_pattern = pattern;
+	led_pattern = pattern;
 	leds_off();
 }
 
@@ -91,18 +91,18 @@ void leds_off(void)
 
 
 /**
- * Task that handles blinking the heartbeat LED.
+ * Task that handles LED updates.
  */
-void heartbeat_task(void)
+void led_task(void)
 {
 	static uint32_t start_ms = 0;
 
 	// Blink every interval ms
-	if ( board_millis() - start_ms < blink_pattern) {
+	if ( board_millis() - start_ms < led_pattern) {
 		return; // not enough time
 	}
 
-	start_ms += blink_pattern;
+	start_ms += led_pattern;
 	led_toggle(LED_STATUS);
 
 }
diff --git a/firmware/src/boards/qtpy/fpga.c b/firmware/src/boards/qtpy/fpga.c
index 59aecc0..82c8de9 100644
--- a/firmware/src/boards/qtpy/fpga.c
+++ b/firmware/src/boards/qtpy/fpga.c
@@ -10,6 +10,7 @@
 
 #include "apollo_board.h"
 #include "jtag.h"
+#include "fpga.h"
 
 // List of pins used for FPGA interfacing.
 
@@ -80,4 +81,7 @@ void trigger_fpga_reconfiguration(void)
 
 	gpio_set_pin_level(PIN_PROG, true);
 	gpio_set_pin_direction(PIN_PROG, GPIO_DIRECTION_IN);
+
+	// Update internal state.
+	fpga_online = true;
 }
diff --git a/firmware/src/boards/qtpy/fpga_adv.c b/firmware/src/boards/qtpy/fpga_adv.c
index b2c85f9..5a62561 100644
--- a/firmware/src/boards/qtpy/fpga_adv.c
+++ b/firmware/src/boards/qtpy/fpga_adv.c
@@ -6,6 +6,7 @@
  * Copyright (c) 2023 Great Scott Gadgets <info@greatscottgadgets.com>
  * SPDX-License-Identifier: BSD-3-Clause
  */
+#include <stdbool.h>
 
 /**
  * Initialize FPGA_ADV receive-only serial port
@@ -27,3 +28,11 @@ void fpga_adv_task(void)
 void honor_fpga_adv(void)
 {
 }
+
+/**
+ * True if we received an advertisement message within the last time window.
+ */
+bool fpga_requesting_port(void)
+{
+    return false;
+}
diff --git a/firmware/src/boards/qtpy/led.c b/firmware/src/boards/qtpy/led.c
index 68a1c13..4ca10b6 100644
--- a/firmware/src/boards/qtpy/led.c
+++ b/firmware/src/boards/qtpy/led.c
@@ -22,15 +22,15 @@
 
 
 /** Store the current LED blink pattern. */
-static blink_pattern_t blink_pattern = BLINK_IDLE;
+static led_pattern_t led_pattern = LED_IDLE;
 
 
 /**
- * Sets the active LED blink pattern.
+ * Sets the active LED pattern.
  */
-void led_set_blink_pattern(blink_pattern_t pattern)
+void led_set_pattern(led_pattern_t pattern)
 {
-	blink_pattern = pattern;
+	led_pattern = pattern;
 	leds_off();
 }
 
@@ -105,31 +105,31 @@ static void display_led_number(uint8_t number)
 
 
 /**
- * Task that handles blinking the heartbeat LED.
+ * Task that handles LED updates.
  */
-void heartbeat_task(void)
+void led_task(void)
 {
   static uint32_t start_ms = 0;
   static uint8_t active_led = 0;
   static bool count_up = true;
 
   // Blink every interval ms
-  if ( board_millis() - start_ms < blink_pattern) return; // not enough time
-  start_ms += blink_pattern;
+  if ( board_millis() - start_ms < led_pattern) return; // not enough time
+  start_ms += led_pattern;
 
-  switch (blink_pattern) {
+  switch (led_pattern) {
 
     // Standard blink pattern for when the device is idle.
     // Indicates that the device's JTAG lines are un-pulled.
-    case BLINK_IDLE:
+    case LED_IDLE:
       led_toggle(LED_E);
       break;
 
     // Blink patterns for when the device is being used for JTAG
     // operation. When these are on, the uC is driving the JTAG lines,
     // so the JTAG header probably shouldn't used to drive the lines.
-    case BLINK_JTAG_CONNECTED:
-    case BLINK_JTAG_UPLOADING:
+    case LED_JTAG_CONNECTED:
+    case LED_JTAG_UPLOADING:
 
       // Sweep back and forth.
       if (active_led == 0xFF) {
@@ -148,7 +148,7 @@ void heartbeat_task(void)
 
     // Blink patterns for when the device is being used for SPI flash access.
     // When these are displayed,
-    case BLINK_FLASH_CONNECTED:
+    case LED_FLASH_CONNECTED:
 
       if (active_led == 5) {
         active_led = 0;
diff --git a/firmware/src/boards/samd11_xplained/fpga.c b/firmware/src/boards/samd11_xplained/fpga.c
index 17a1151..929345a 100644
--- a/firmware/src/boards/samd11_xplained/fpga.c
+++ b/firmware/src/boards/samd11_xplained/fpga.c
@@ -9,6 +9,7 @@
 #include <hal/include/hal_gpio.h>
 
 #include "jtag.h"
+#include "fpga.h"
 
 // List of pins used for FPGA interfacing.
 enum {
@@ -73,4 +74,7 @@ void trigger_fpga_reconfiguration(void)
 
 	gpio_set_pin_level(PIN_PROG, true);
 	gpio_set_pin_direction(PIN_PROG, GPIO_DIRECTION_IN);
+
+	// Update internal state.
+	fpga_online = true;
 }
diff --git a/firmware/src/boards/samd11_xplained/fpga_adv.c b/firmware/src/boards/samd11_xplained/fpga_adv.c
index b2c85f9..5a62561 100644
--- a/firmware/src/boards/samd11_xplained/fpga_adv.c
+++ b/firmware/src/boards/samd11_xplained/fpga_adv.c
@@ -6,6 +6,7 @@
  * Copyright (c) 2023 Great Scott Gadgets <info@greatscottgadgets.com>
  * SPDX-License-Identifier: BSD-3-Clause
  */
+#include <stdbool.h>
 
 /**
  * Initialize FPGA_ADV receive-only serial port
@@ -27,3 +28,11 @@ void fpga_adv_task(void)
 void honor_fpga_adv(void)
 {
 }
+
+/**
+ * True if we received an advertisement message within the last time window.
+ */
+bool fpga_requesting_port(void)
+{
+    return false;
+}
diff --git a/firmware/src/boards/samd11_xplained/led.c b/firmware/src/boards/samd11_xplained/led.c
index 0ce2bc8..a6d30ac 100644
--- a/firmware/src/boards/samd11_xplained/led.c
+++ b/firmware/src/boards/samd11_xplained/led.c
@@ -21,15 +21,15 @@
 
 
 /** Store the current LED blink pattern. */
-static blink_pattern_t blink_pattern = BLINK_IDLE;
+static led_pattern_t led_pattern = LED_IDLE;
 
 
 /**
- * Sets the active LED blink pattern.
+ * Sets the active LED pattern.
  */
-void led_set_blink_pattern(blink_pattern_t pattern)
+void led_set_pattern(led_pattern_t pattern)
 {
-	blink_pattern = pattern;
+	led_pattern = pattern;
 	leds_off();
 }
 
@@ -91,18 +91,18 @@ void leds_off(void)
 
 
 /**
- * Task that handles blinking the heartbeat LED.
+ * Task that handles LED updates.
  */
-void heartbeat_task(void)
+void led_task(void)
 {
 	static uint32_t start_ms = 0;
 
 	// Blink every interval ms
-	if ( board_millis() - start_ms < blink_pattern) {
+	if ( board_millis() - start_ms < led_pattern) {
 		return; // not enough time
 	}
 
-	start_ms += blink_pattern;
+	start_ms += led_pattern;
 	led_toggle(LED_STATUS);
 
 }
diff --git a/firmware/src/debug_spi.c b/firmware/src/debug_spi.c
index cf09c34..c2fb5b7 100644
--- a/firmware/src/debug_spi.c
+++ b/firmware/src/debug_spi.c
@@ -200,7 +200,7 @@ bool handle_take_configuration_spi(uint8_t rhport, tusb_control_request_t const*
 #endif
 
 	// ... and set a blink pattern accordingly.
-	led_set_blink_pattern(BLINK_FLASH_CONNECTED);
+	led_set_pattern(LED_FLASH_CONNECTED);
 	return tud_control_xfer(rhport, request, NULL, 0);
 }
 
@@ -217,7 +217,7 @@ bool handle_release_configuration_spi(uint8_t rhport, tusb_control_request_t con
 	gpio_set_pin_pull_mode(PIN_FLASH_CS, GPIO_PULL_UP);
 #endif
 
-	led_set_blink_pattern(BLINK_IDLE);
+	led_set_pattern(LED_IDLE);
 
 	return tud_control_xfer(rhport, request, NULL, 0);
 }
diff --git a/firmware/src/fpga.c b/firmware/src/fpga.c
index 90e9527..d0aea32 100644
--- a/firmware/src/fpga.c
+++ b/firmware/src/fpga.c
@@ -12,6 +12,7 @@
 
 extern uint8_t jtag_out_buffer[256];
 
+bool fpga_online = false;
 
 /*
  * ECP5 opcode that enables offline configuration mode
@@ -36,4 +37,15 @@ void force_fpga_offline(void)
 	jtag_go_to_state(STATE_RUN_TEST_IDLE);
 	jtag_wait_time(2);
 	jtag_deinit();
+
+	// Update internal state.
+	fpga_online = false;
+}
+
+/*
+ * True after FPGA reconfiguration, false after forcing FPGA offline.
+ */
+bool fpga_is_online(void)
+{
+	return fpga_online;
 }
diff --git a/firmware/src/fpga.h b/firmware/src/fpga.h
index e4bb9c3..e1637f3 100644
--- a/firmware/src/fpga.h
+++ b/firmware/src/fpga.h
@@ -10,6 +10,8 @@
 #ifndef __FPGA_H__
 #define __FPGA_H__
 
+extern bool fpga_online;
+
 /**
  * Sets up the I/O pins needed to configure the FPGA.
  */
@@ -32,4 +34,9 @@ void trigger_fpga_reconfiguration(void);
  */
 void force_fpga_offline(void);
 
+/*
+ * True after FPGA reconfiguration, false after forcing FPGA offline.
+ */
+bool fpga_is_online(void);
+
 #endif
diff --git a/firmware/src/fpga_adv.h b/firmware/src/fpga_adv.h
index 6e9b5ab..1585230 100644
--- a/firmware/src/fpga_adv.h
+++ b/firmware/src/fpga_adv.h
@@ -25,5 +25,9 @@ void fpga_adv_task(void);
  */
 void honor_fpga_adv(void);
 
+/**
+ * True if we received an advertisement message within the last time window.
+ */
+bool fpga_requesting_port(void);
 
 #endif
diff --git a/firmware/src/jtag.c b/firmware/src/jtag.c
index 88a1ef6..0d798d9 100644
--- a/firmware/src/jtag.c
+++ b/firmware/src/jtag.c
@@ -20,6 +20,10 @@
 #include "jtag.h"
 #include "uart.h"
 #include "spi.h"
+#include "fpga.h"
+
+#define ISC_ENABLE  0xC6
+#define ISC_DISABLE 0x26
 
 
 // JTAG comms buffers.
@@ -109,6 +113,16 @@ bool handle_jtag_request_set_out_buffer(uint8_t rhport, tusb_control_request_t c
 		return false;
 	}
 
+	// HACK: check the buffer for commands that affect the FPGA configuration state.
+    if (request->wLength == 1) {
+		if (jtag_out_buffer[0] == ISC_ENABLE) {
+			fpga_online = false;
+		}
+		if (jtag_out_buffer[0] == ISC_DISABLE) {
+			fpga_online = true;
+		}
+    }
+
 	// Copy the relevant data into our OUT buffer.
 	return tud_control_xfer(rhport, request, jtag_out_buffer, request->wLength);
 }
@@ -191,7 +205,7 @@ bool handle_jtag_get_state(uint8_t rhport, tusb_control_request_t const* request
  */
 bool handle_jtag_start(uint8_t rhport, tusb_control_request_t const* request)
 {
-	led_set_blink_pattern(BLINK_JTAG_CONNECTED);
+	led_set_pattern(LED_JTAG_CONNECTED);
 	jtag_init();
 
 	return tud_control_xfer(rhport, request, NULL, 0);
@@ -203,7 +217,7 @@ bool handle_jtag_start(uint8_t rhport, tusb_control_request_t const* request)
  */
 bool handle_jtag_stop(uint8_t rhport, tusb_control_request_t const* request)
 {
-	led_set_blink_pattern(BLINK_IDLE);
+	led_set_pattern(LED_IDLE);
 	jtag_deinit();
 
 	return tud_control_xfer(rhport, request, NULL, 0);
diff --git a/firmware/src/led.h b/firmware/src/led.h
index c643089..b5d1243 100644
--- a/firmware/src/led.h
+++ b/firmware/src/led.h
@@ -22,21 +22,21 @@
  * with different semantic meanings.
  */
 typedef enum {
-  BLINK_IDLE = 500,
-  BLINK_JTAG_CONNECTED = 150,
-  BLINK_JTAG_UPLOADING = 50,
+  LED_IDLE = 500,
+  LED_JTAG_CONNECTED = 150,
+  LED_JTAG_UPLOADING = 50,
 
-  BLINK_FLASH_CONNECTED = 130,
-} blink_pattern_t;
+  LED_FLASH_CONNECTED = 130,
+} led_pattern_t;
 
 
 
 /**
- * Sets the active LED blink pattern.
+ * Sets the active LED pattern.
  *
- * See @ref blink_pattern_t for the meaning of the pattern argument.
+ * See @ref led_pattern_t for the meaning of the pattern argument.
  */
-void led_set_blink_pattern(blink_pattern_t pattern);
+void led_set_pattern(led_pattern_t pattern);
 
 
 /**
@@ -76,8 +76,8 @@ void led_set(led_t led, bool on);
 
 
 /**
- * Task that handles blinking the heartbeat LED.
+ * Task that handles LED updates.
  */
-void heartbeat_task(void);
+void led_task(void);
 
 #endif
diff --git a/firmware/src/main.c b/firmware/src/main.c
index ab3bfba..88f0b25 100644
--- a/firmware/src/main.c
+++ b/firmware/src/main.c
@@ -85,7 +85,7 @@ int main(void)
 	while (1) {
 		tud_task(); // tinyusb device task
 		console_task();
-		heartbeat_task();
+		led_task();
 		button_task();
 		fpga_adv_task();
 	}
diff --git a/firmware/src/usb_switch.c b/firmware/src/usb_switch.c
index 2b38d54..190f92c 100644
--- a/firmware/src/usb_switch.c
+++ b/firmware/src/usb_switch.c
@@ -63,3 +63,16 @@ void take_over_usb(void)
 	switch_state = SWITCH_MCU;
 #endif
 }
+
+
+/**
+ * True if the USB switch handed over the port to the FPGA. 
+ */
+bool fpga_controls_usb_port(void)
+{
+#ifdef BOARD_HAS_USB_SWITCH
+	return switch_state == SWITCH_FPGA;
+#else
+	return false;
+#endif
+}
diff --git a/firmware/src/usb_switch.h b/firmware/src/usb_switch.h
index 7049ae2..d17f36b 100644
--- a/firmware/src/usb_switch.h
+++ b/firmware/src/usb_switch.h
@@ -10,6 +10,7 @@
 #ifndef __USB_SWITCH_H__
 #define __USB_SWITCH_H__
 
+#include <stdbool.h>
 
 /**
  * Hand off shared USB port to FPGA.
@@ -21,5 +22,8 @@ void hand_off_usb(void);
  */
 void take_over_usb(void);
 
-
+/**
+ * True if the USB switch handed over the port to the FPGA. 
+ */
+bool fpga_controls_usb_port(void);
 #endif
diff --git a/firmware/src/vendor.c b/firmware/src/vendor.c
index 6c20f9f..f027704 100644
--- a/firmware/src/vendor.c
+++ b/firmware/src/vendor.c
@@ -116,7 +116,7 @@ bool handle_get_id_request(uint8_t rhport, tusb_control_request_t const* request
  */
 bool handle_set_led_pattern(uint8_t rhport, tusb_control_request_t const* request)
 {
-	led_set_blink_pattern(request->wValue);
+	led_set_pattern(request->wValue);
 	return tud_control_xfer(rhport, request, NULL, 0);
 }