Merge pull request #374 from piotrmalek/master

Improve bootloader version parsing from GIT_VERSION

.github/workflows/githubci.yml

@@ -1,13 +1,18 @@
 name: Build
 
 on:
+  workflow_dispatch:
   pull_request:
   push:
-  repository_dispatch:
+    branches: [ master ]
   release:
     types:
       - created
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   set-matrix:
     runs-on: ubuntu-latest

.gitignore

@@ -56,6 +56,7 @@ dkms.conf
 
 segger/Output
 _build/
+cmake-build-*/
 bin/
 *.emSession
 *.jlink
@@ -68,4 +69,3 @@ Makefile.user
 
 # Exclude all SoftDevice S340 files
 lib/softdevice/s340*
-

AGENTS.md

@@ -1,25 +1,102 @@
 # Agent Instructions
 
+This file provides guidance to AI agents when working with code in this repository.
+
+## Project Overview
+
+CDC/DFU/UF2 bootloader for Nordic nRF52 microcontrollers (nRF52832, nRF52833, nRF52840). Supports DFU over Serial, BLE OTA, and USB mass storage (UF2). Runs on 60+ boards.
+
 ## Style
-- Follow the repo `.clang-format` when making changes.
+
+Follow the repo `.clang-format` when making changes.
 
 ## Build / Verify
-- Prefer CMake for testing/verification.
-- Always build both boards during verification:
-  - `feather_nrf52832`
-  - `feather_nrf52840_express`
+
+Default board: `feather_nrf52840_express`. Always verify changes against both boards:
+- `feather_nrf52840_express` (nRF52840)
+- `feather_nrf52832` (nRF52832)
 
 ### CMake (preferred)
 ```bash
-cmake -S . -B cmake-build-feather_nrf52832 -DBOARD=feather_nrf52832
-cmake --build cmake-build-feather_nrf52832
-
 cmake -S . -B cmake-build-feather_nrf52840_express -DBOARD=feather_nrf52840_express
 cmake --build cmake-build-feather_nrf52840_express
+
+cmake -S . -B cmake-build-feather_nrf52832 -DBOARD=feather_nrf52832
+cmake --build cmake-build-feather_nrf52832
 ```
 
 ### Make (alternate)
 ```bash
-make BOARD=feather_nrf52832 all
 make BOARD=feather_nrf52840_express all
+make BOARD=feather_nrf52832 all
 ```
+
+### Flashing
+```bash
+make BOARD={board} flash       # Flash via JLink
+make BOARD={board} flash-dfu   # Flash via Serial/CDC DFU
+make BOARD={board} flash-sd    # Flash SoftDevice only
+```
+
+### Build all boards
+```bash
+python3 tools/build_all.py
+```
+
+## Architecture
+
+### MCU Variants and SoftDevices
+- **nrf52** (nRF52832): UART-only bootloader, default SoftDevice s132 v6.1.1
+- **nrf52833**: USB support, default SoftDevice s140 v7.3.0
+- **nrf52840**: Full USB + OTA, default SoftDevice s140 v6.1.1
+- Boards may override `SD_NAME`/`SD_VERSION` in their `board.mk`
+
+### Key Source Structure
+- `src/main.c` — Bootloader entry point, DFU mode detection, LED/button init
+- `src/dfu_init.c` — DFU packet validation, CRC/signature verification
+- `src/dfu_ble_svc.c` — BLE DFU service
+- `src/flash_nrf5x.c` — Flash memory operations
+- `src/boards/boards.c` — Board abstraction (LED control, buttons, timing)
+- `src/usb/` — USB stack (nRF52833/nRF52840): CDC serial, MSC storage, UF2 handler
+- `src/usb/uf2/ghostfat.c` — Virtual FAT filesystem for UF2 drag-and-drop
+
+### Board Definition System
+
+Each board lives in `src/boards/{board_name}/` with:
+- `board.h` — Pin definitions, LED/button assignments, USB VID/PID, UF2 metadata
+- `board.mk` — Makefile variable `MCU_SUB_VARIANT` (nrf52, nrf52833, or nrf52840)
+- `board.cmake` — CMake variable `MCU_VARIANT`
+- `pinconfig.c` — CF2 bootloader configuration (flash/RAM size, UF2 family ID)
+
+### Memory Layout (linker scripts in `linker/`)
+- Bootloader occupies ~38KB near end of flash (e.g., 0xF4000–0xFD800 on nRF52840)
+- No heap (`__HEAP_SIZE=0`), static allocation only
+- Special sections: double-reset detection word, bond info for OTA, MBR params, bootloader settings
+
+### Submodules (`lib/`)
+- `tinyusb` — USB device stack
+- `nrfx` — Nordic HAL drivers
+- `uf2` — UF2 format tools
+- `tinycrypt` — Crypto (only when `SIGNED_FW=1`)
+- `sdk/`, `sdk11/` — Nordic SDK libraries
+- `softdevice/` — Precompiled Bluetooth stack binaries
+
+### Compile-Time Feature Flags
+- `SIGNED_FW` — Require signed firmware (disables UF2 unless `FORCE_UF2=1`)
+- `DUALBANK_FW` — Dual-bank updates
+- `DEFAULT_TO_OTA_DFU` — Default to BLE OTA instead of serial DFU
+- `DEBUG` — Enable RTT debugging, larger bootloader region
+
+## PR Review Checklist
+
+- **VID/PID assignment**: When a PR adds or modifies a board, verify `USB_DESC_VID`/`USB_DESC_UF2_PID` in `board.h`. New boards should use unique values. The Adafruit VID `0x239A` is reserved for Adafruit-allocated boards; third-party boards must use their own VID. Some legacy boards intentionally share a VID/PID with a reference board (see `// Shared VID/PID with ...` comments) — these are pending cleanup, not a template for new boards.
+
+## CI
+
+GitHub Actions (`.github/workflows/githubci.yml`) builds all boards in parallel using a matrix generated from `src/boards/` directory names. On release, artifacts (zip, hex, uf2) are uploaded as release assets.
+
+## Required Toolchain
+
+- `arm-none-eabi-gcc` (tested with 12.3.1)
+- Python 3 with: `adafruit-nrfutil`, `intelhex`
+- `nrfjprog` (for JLink flashing)

CMakeLists.txt

@@ -316,13 +316,22 @@ endif()
 execute_process(COMMAND git describe --dirty --always --tags OUTPUT_VARIABLE GIT_VERSION)
 string(STRIP ${GIT_VERSION} GIT_VERSION)
 
-string(REPLACE "-" ";" RELEASE_VERSION ${GIT_VERSION})
-list(GET RELEASE_VERSION 0 RELEASE_VERSION)
-string(REPLACE "." ";" RELEASE_VERSION ${RELEASE_VERSION})
-list(GET RELEASE_VERSION 0 RELEASE_VERSION_MAJOR)
-list(GET RELEASE_VERSION 1 RELEASE_VERSION_MINOR)
-list(GET RELEASE_VERSION 2 RELEASE_VERSION_PATCH)
-math(EXPR MK_BOOTLOADER_VERSION "(${RELEASE_VERSION_MAJOR} << 16) + (${RELEASE_VERSION_MINOR} << 8) + ${RELEASE_VERSION_PATCH}")
+# Extract semantic version numbers (MAJOR.MINOR.PATCH) from GIT_VERSION.
+# Supports tags like:
+#   v1.2.3
+#   1.2.3
+#   1.2.3-147-gd71abcd
+# If the version string does not match MAJOR.MINOR.PATCH, defaults to 0.0.0.
+if(GIT_VERSION MATCHES "^v?([0-9]+)\\.([0-9]+)\\.([0-9]+)")
+  set(RELEASE_VERSION_MAJOR ${CMAKE_MATCH_1})
+  set(RELEASE_VERSION_MINOR ${CMAKE_MATCH_2})
+  set(RELEASE_VERSION_PATCH ${CMAKE_MATCH_3})
+else()
+  set(RELEASE_VERSION_MAJOR 0)
+  set(RELEASE_VERSION_MINOR 0)
+  set(RELEASE_VERSION_PATCH 0)
+endif()
+math(EXPR MK_BOOTLOADER_VERSION "((${RELEASE_VERSION_MAJOR} << 16) | (${RELEASE_VERSION_MINOR} << 8) | ${RELEASE_VERSION_PATCH})")
 
 cmake_print_variables(GIT_VERSION MK_BOOTLOADER_VERSION)
 

Makefile

@@ -262,7 +262,7 @@ IPATH += \
   src/cmsis/include \
   src/usb \
   $(TUSB_PATH)
-  
+
 ifeq ($(SIGNED_FW), 1)
 IPATH += \
   $(TCRYPT_PATH)/include
@@ -376,8 +376,25 @@ ifeq ($(DEFAULT_TO_OTA_DFU), 1)
 CFLAGS += -DDEFAULT_TO_OTA_DFU
 endif
 
-_VER = $(subst ., ,$(word 1, $(subst -, ,$(GIT_VERSION))))
-CFLAGS += -DMK_BOOTLOADER_VERSION='($(word 1,$(_VER)) << 16) + ($(word 2,$(_VER)) << 8) + $(word 3,$(_VER))'
+# Extract semantic version numbers (MAJOR.MINOR.PATCH) from GIT_VERSION.
+# Supports tags like:
+#   v1.2.3
+#   1.2.3
+#   1.2.3-147-gd71abcd
+# If the version string does not match MAJOR.MINOR.PATCH, defaults to 0.0.0.
+_VER3 := $(shell echo "$(GIT_VERSION)" | sed -E 's/^v?([0-9]+)\.([0-9]+)\.([0-9]+).*/\1 \2 \3/; t; s/.*/0 0 0/')
+
+# Split extracted version into individual numeric components
+_VER_MAJ := $(word 1,$(_VER3))
+_VER_MIN := $(word 2,$(_VER3))
+_VER_PAT := $(word 3,$(_VER3))
+
+# Pack MAJOR.MINOR.PATCH into a single 32-bit integer:
+#   [31:16] MAJOR
+#   [15:8]  MINOR
+#   [7:0]   PATCH
+# This value is stored in the bootloader version register and must be a valid C integer constant.
+CFLAGS += -DMK_BOOTLOADER_VERSION='((($(_VER_MAJ)<<16)|($(_VER_MIN)<<8)|($(_VER_PAT))))'
 
 # Debug option use RTT for printf
 ifeq ($(DEBUG), 1)

lib/sdk11/components/libraries/bootloader_dfu/bootloader.c

@@ -51,9 +51,31 @@ typedef enum
 static pstorage_handle_t        m_bootsettings_handle;  /**< Pstorage handle to use for registration and identifying the bootloader module on subsequent calls to the pstorage module for load and store of bootloader setting in flash. */
 static bootloader_status_t      m_update_status;        /**< Current update status for the bootloader module to ensure correct behaviour when updating settings and when update completes. */
 static bool m_cancel_timeout_on_usb; /**< If set the timeout is cancelled when USB is enumerated. Otherwise, the timeout is only cancelled when DFU update is started. */
+static bool m_usb_was_mounted; /**< Tracks whether the USB DFU session was ever enumerated so we can exit when cable is later removed. */
+static bool m_startup_dfu_has_activity; /**< Tracks whether any valid serial or UF2 update traffic has started. */
 
 APP_TIMER_DEF( _dfu_startup_timer );
-volatile bool dfu_startup_packet_received = false;
+
+static void bootloader_timeout_startup_dfu(void)
+{
+    if (!m_startup_dfu_has_activity)
+    {
+        dfu_update_status_t update_status;
+        update_status.status_code = DFU_TIMEOUT;
+
+        bootloader_dfu_update_process(update_status);
+    }
+}
+
+void bootloader_dfu_activity_mark(void)
+{
+    m_startup_dfu_has_activity = true;
+}
+
+void bootloader_mark_usb_mounted(void)
+{
+    m_usb_was_mounted = true;
+}
 
 /**@brief   Function for handling callbacks from pstorage module.
  *
@@ -82,22 +104,17 @@ static void pstorage_callback_handler(pstorage_handle_t * p_handle,
 static void dfu_startup_timer_handler(void * p_context)
 {
 #ifdef NRF_USBD
-  if (m_cancel_timeout_on_usb && tud_mounted())
+  // If host enumerated the device, keep waiting — m_usb_was_mounted was set
+  // by tud_mount_cb() and the unplug path in wait_for_events() will handle exit.
+  if (m_cancel_timeout_on_usb && m_usb_was_mounted)
   {
     return;
   }
 #endif
 
   // nRF52832 forced DFU on startup
-  // No packets are received within timeout, exit DFU mode
-  // dfu_startup_packet_received is set by process_dfu_packet() in dfu_transport_serial.c
-  if (!dfu_startup_packet_received)
-  {
-    dfu_update_status_t update_status;
-    update_status.status_code = DFU_TIMEOUT;
-
-    bootloader_dfu_update_process(update_status);
-  }
+  // No update activity is received within timeout, exit DFU mode
+  bootloader_timeout_startup_dfu();
 }
 
 /**@brief   Function for waiting for events.
@@ -133,6 +150,14 @@ static void wait_for_events(void)
       tud_task();
       tud_cdc_write_flush();
     }
+
+    // Exit startup DFU once USB was actually unplugged (VBUS gone), not on a
+    // host-side re-enumeration or temporary unmount.
+    if (m_cancel_timeout_on_usb && m_usb_was_mounted &&
+        !(NRF_POWER->USBREGSTATUS & POWER_USBREGSTATUS_VBUSDETECT_Msk))
+    {
+      bootloader_timeout_startup_dfu();
+    }
 #endif
 
     if ((m_update_status == BOOTLOADER_COMPLETE) ||
@@ -149,23 +174,22 @@ static void wait_for_events(void)
 
 bool bootloader_app_is_valid(void)
 {
-  bool success = false;
   uint32_t const app_addr = DFU_BANK_0_REGION_START;
-
-  bootloader_settings_t const *p_bootloader_settings;
-  bootloader_util_settings_get(&p_bootloader_settings);
+  uint32_t const sp_addr = *((uint32_t*)app_addr);
+  uint32_t const reset_addr = *((uint32_t*)(app_addr + 4));
 
   enum { EMPTY_FLASH = 0xFFFFFFFFUL };
 
-  // Application is invalid if first 2 words are all 0xFFFFFFF
-  if ( *((uint32_t *)app_addr    ) == EMPTY_FLASH &&
-       *((uint32_t *)(app_addr+4)) == EMPTY_FLASH )
+  if (sp_addr == EMPTY_FLASH && reset_addr == EMPTY_FLASH)
   {
     return false;
   }
 
-  // The application in CODE region 1 is flagged as valid during update.
-  if ( p_bootloader_settings->bank_0 == BANK_VALID_APP )
+  bootloader_settings_t const * p_bootloader_settings;
+  bootloader_util_settings_get(&p_bootloader_settings);
+
+  // Primary path: a prior DFU flagged bank 0 as valid.
+  if (p_bootloader_settings->bank_0 == BANK_VALID_APP)
   {
     uint16_t image_crc = 0;
 
@@ -177,10 +201,26 @@ bool bootloader_app_is_valid(void)
                                 NULL);
     }
 
-    success = (image_crc == p_bootloader_settings->bank_0_crc);
+    return (image_crc == p_bootloader_settings->bank_0_crc);
   }
 
-  return success;
+  // Fallback for debugger-flashed apps: settings page is erased (bank_0 = 0xFFFF)
+  // but an app may still have been written to bank 0 directly. Accept it if its
+  // Cortex-M vector table is plausible: initial SP within RAM, reset vector
+  // within app flash region with the Thumb bit set. The SP upper bound is
+  // inclusive because the empty-descending stack initializes one past RAM end.
+  if (p_bootloader_settings->bank_0 == 0xFFFF)
+  {
+    uint32_t const ram_start = 0x20000000UL;
+    uint32_t const ram_end = ram_start + (NRF_FICR->INFO.RAM << 10u);
+    bool const sp_valid = (sp_addr >= ram_start) && (sp_addr <= ram_end) && ((sp_addr & 3U) == 0);
+    bool const reset_in_app = (reset_addr & 1U) &&
+      (reset_addr >= app_addr) &&
+      (reset_addr < BOOTLOADER_REGION_START);
+    return sp_valid && reset_in_app;
+  }
+
+  return false;
 }
 
 
@@ -358,6 +398,8 @@ uint32_t bootloader_dfu_start(bool ota, uint32_t timeout_ms, bool cancel_timeout
   uint32_t err_code;
 
   m_cancel_timeout_on_usb = cancel_timeout_on_usb && !ota;
+  m_usb_was_mounted = false;
+  m_startup_dfu_has_activity = false;
 
   // Clear swap if banked update is used.
   err_code = dfu_init();
@@ -373,8 +415,6 @@ uint32_t bootloader_dfu_start(bool ota, uint32_t timeout_ms, bool cancel_timeout
     // - Makecode single tap reset but no enumerated (battery power)
     if ( timeout_ms )
     {
-      dfu_startup_packet_received = false;
-
       app_timer_create(&_dfu_startup_timer, APP_TIMER_MODE_SINGLE_SHOT, dfu_startup_timer_handler);
       app_timer_start(_dfu_startup_timer, APP_TIMER_TICKS(timeout_ms), NULL);
     }

lib/sdk11/components/libraries/bootloader_dfu/bootloader.h

@@ -74,6 +74,20 @@ void bootloader_settings_get(bootloader_settings_t * const p_settings);
  */
 void bootloader_dfu_update_process(dfu_update_status_t update_status);
 
+/**@brief Mark that startup DFU has received valid update activity.
+ *
+ * @details This suppresses the startup timeout or USB unplug fallback that is only
+ *          meant for the "entered bootloader, but never started an update" case.
+ */
+void bootloader_dfu_activity_mark(void);
+
+/**@brief Mark that the USB DFU session was enumerated by a host.
+ *
+ * @details Called from tud_mount_cb(). Enables the USB-unplug exit path in
+ *          wait_for_events(), which exits startup DFU once VBUS is removed.
+ */
+void bootloader_mark_usb_mounted(void);
+
 /**@brief Function getting state of SoftDevice update in progress.
  *        After a successfull SoftDevice transfer the system restarts in orderto disable SoftDevice
  *        and complete the update.

lib/sdk11/components/libraries/bootloader_dfu/bootloader_util.c

@@ -11,9 +11,12 @@
  */
 
 #include "bootloader_util.h"
-#include <stdint.h>
-#include <string.h>
+#include "dfu_types.h"
+#include "nrf_peripherals.h"
 
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
 
 /**
  * @brief Function for aborting current application/bootloader jump to to other app/bootloader.
@@ -164,8 +167,76 @@ static inline void bootloader_util_reset(uint32_t start_addr)
 #error Compiler not supported.
 #endif
 
+// protect flash region from write access
+static uint32_t bootloader_util_flash_protect(uint32_t address, uint32_t size) {
+  if ((size & (CODE_PAGE_SIZE - 1)) || (address & (CODE_PAGE_SIZE - 1)) || (address > BOOTLOADER_SETTINGS_ADDRESS)) {
+    return NRF_ERROR_INVALID_PARAM;
+  }
 
-void bootloader_util_app_start(uint32_t start_addr)
-{
-    bootloader_util_reset(start_addr);
+#if defined(ACL_PRESENT)
+  // Protect using ACL.
+  static uint32_t acl_instance = 0;
+
+  volatile ACL_ACL_Type *p_acl;
+  const uint32_t         mask = (ACL_ACL_PERM_WRITE_Disable << ACL_ACL_PERM_WRITE_Pos);
+
+  do {
+    if (acl_instance >= ACL_REGIONS_COUNT) {
+      return NRF_ERROR_NO_MEM;
+    }
+
+    p_acl       = &NRF_ACL->ACL[acl_instance];
+    p_acl->ADDR = address;
+    p_acl->SIZE = size;
+    p_acl->PERM = mask;
+
+    acl_instance++;
+
+  } while (p_acl->ADDR != address || p_acl->SIZE != size ||
+           p_acl->PERM != mask); // Check whether the acl_instance has been used before.
+
+#elif defined(BPROT_PRESENT)
+  // Protect using BPROT. BPROT does not support read protection.
+  uint32_t pagenum_start = address / CODE_PAGE_SIZE;
+  uint32_t pagenum_end   = pagenum_start + ((size - 1) / CODE_PAGE_SIZE);
+
+  for (uint32_t i = pagenum_start; i <= pagenum_end; i++) {
+    uint32_t config_index = i / 32;
+    uint32_t mask         = (1 << (i - config_index * 32));
+
+    switch (config_index) {
+      case 0:
+        NRF_BPROT->CONFIG0 = mask;
+        break;
+      case 1:
+        NRF_BPROT->CONFIG1 = mask;
+        break;
+  #if BPROT_REGIONS_NUM > 64
+      case 2:
+        NRF_BPROT->CONFIG2 = mask;
+        break;
+      case 3:
+        NRF_BPROT->CONFIG3 = mask;
+        break;
+  #endif
+    }
+  }
+
+#endif
+
+  return NRF_SUCCESS;
+}
+
+void bootloader_util_app_start(uint32_t start_addr) {
+  // Protect MBR against user writes
+  bootloader_util_flash_protect(0, MBR_SIZE);
+
+  // Size of the bootloader flash area to protect (Bootloader + MBR params + Bootloader settings)
+  const uint32_t area_size = BOOTLOADER_SETTINGS_ADDRESS + CODE_PAGE_SIZE - BOOTLOADER_REGION_START;
+
+  // Protect bootloader code and params pages against user writes
+  bootloader_util_flash_protect(BOOTLOADER_REGION_START, area_size);
+
+  // Jump to user application
+  bootloader_util_reset(start_addr);
 }

lib/sdk11/components/libraries/bootloader_dfu/dfu_transport_serial.c

@@ -12,6 +12,7 @@
 
 #include "dfu_transport.h"
 #include <stddef.h>
+#include "bootloader.h"
 #include "dfu.h"
 #include <dfu_types.h>
 #include "app_error.h"
@@ -197,9 +198,8 @@ static void process_dfu_packet(void * p_event_data, uint16_t event_size)
     uint32_t              index;
     dfu_update_packet_t * packet;
 
-    // Adafruit modification for startup dfu
-    extern bool dfu_startup_packet_received;
-    dfu_startup_packet_received = true;
+    // Mark that startup DFU has transitioned into a real update flow.
+    bootloader_dfu_activity_mark();
 
     while (false == DATA_QUEUE_EMPTY())
     {

lib/sdk11/components/libraries/bootloader_dfu/dfu_types.h

@@ -20,6 +20,37 @@
  * @brief Device Firmware Update module type and definitions.
  */
 
+/*
+ * Flash layout (nrf52840, see linker/nrf52840.ld):
+ *
+ *  -------------------------
+ * |  Bootloader Settings    |
+ * |          4 KB           |
+ * |-------------------------| 0xFF000 BOOTLOADER_SETTINGS_ADDRESS
+ * |     MBR Params Page     |
+ * |          4 KB           |
+ * |-------------------------| 0xFE000
+ * |    Bootloader Config    |
+ * |          2 KB           |
+ * |-------------------------| 0xFD800
+ * |       Bootloader        |
+ * |          38 KB          |
+ * |-------------------------| 0xF4000 BOOTLOADER_REGION_START
+ * |    App Data Reserved    |
+ * |         40 KB           |
+ * |-------------------------| 0xEA000
+ * |       Application       |
+ * |    Single/ Dual Bank    |
+ * |                         |
+ * |-------------------------| CODE_REGION_1_START
+ * |        SoftDevice       |
+ * |    0x26000 (optional)   |
+ * |-------------------------| 0x01000
+ * |           MBR           |
+ * |          4 KB           |
+ *  -------------------------  0x00000
+ */
+
 #ifndef DFU_TYPES_H__
 #define DFU_TYPES_H__
 

src/boards/xiao_nrf52840_ble/board.h

@@ -28,10 +28,10 @@
 /*------------------------------------------------------------------*/
 /* LED
  *------------------------------------------------------------------*/
-// The board has 3 leds, but changing the number here causes OTA issues.
-#define LEDS_NUMBER      1
-#define LED_PRIMARY_PIN  PINNUM(0, 26)
-#define LED_STATE_ON     0
+#define LEDS_NUMBER       2
+#define LED_PRIMARY_PIN   PINNUM(0, 26) // red
+#define LED_SECONDARY_PIN PINNUM(0, 6) // blue
+#define LED_STATE_ON      0
 
 #define NEOPIXELS_NUMBER 0
 

src/boards/xiao_nrf52840_ble_sense/board.h

@@ -28,10 +28,10 @@
 /*------------------------------------------------------------------*/
 /* LED
  *------------------------------------------------------------------*/
-// The board has 3 leds, but changing the number here causes OTA issues.
-#define LEDS_NUMBER      1
-#define LED_PRIMARY_PIN  PINNUM(0, 26)
-#define LED_STATE_ON     0
+#define LEDS_NUMBER       2
+#define LED_PRIMARY_PIN   PINNUM(0, 26) // red
+#define LED_SECONDARY_PIN PINNUM(0, 6) // blue
+#define LED_STATE_ON      0
 
 #define NEOPIXELS_NUMBER 0
 

src/usb/msc_uf2.c

@@ -145,9 +145,19 @@ int32_t tud_msc_write10_cb (uint8_t lun, uint32_t lba, uint32_t offset, uint8_t*
   uint32_t count = 0;
   while ( count < bufsize )
   {
+    int written;
+
     // Consider non-uf2 block write as successful
     // only break if write_block is busy with flashing (return 0)
-    if ( 0 == write_block(lba, buffer, &_wr_state) ) break;
+    written = write_block(lba, buffer, &_wr_state);
+    if ( written > 0 )
+    {
+      bootloader_dfu_activity_mark();
+    }
+    else if ( written == 0 )
+    {
+      break;
+    }
 
     lba++;
     buffer += 512;

src/usb/usb.c

@@ -33,6 +33,7 @@
 
 #include "uf2/uf2.h"
 #include "boards.h"
+#include "bootloader.h"
 
 //--------------------------------------------------------------------+
 // MACRO TYPEDEF CONSTANT ENUM DECLARATION
@@ -115,6 +116,7 @@ void usb_teardown(void) {
 //--------------------------------------------------------------------+
 void tud_mount_cb(void) {
   led_state(STATE_USB_MOUNTED);
+  bootloader_mark_usb_mounted();
 }
 
 void tud_umount_cb(void) {