remove bootloader binaries, update readme for using adafruit-nrufitl and flashing bootloader

ports/nrf/README.md

@@ -79,6 +79,7 @@ Target Board (BOARD) | Bluetooth Stack (SD)    | Bluetooth Support      | Flash
 pca10040             | s132                    | Peripheral and Scanner | [Segger](#segger-targets)
 feather52832         | s132                    | Peripheral and Scanner | [UART DFU](#dfu-targets)
 pca10056             | s140                    | Peripheral and Scanner | [Segger](#segger-targets)
+feather52840         | s140                    | Peripheral and Scanner | [UART DFU](#dfu-targets)
 
 ## Segger Targets
 
@@ -98,11 +99,9 @@ note: On Linux it might be required to link SEGGER's `libjlinkarm.so` inside nrf
 
 ## DFU Targets
 
-    sudo apt-get install build-essential libffi-dev pkg-config gcc-arm-none-eabi git python python-pip
+run follow command to install [adafruit-nrfutil](https://github.com/adafruit/Adafruit_nRF52_nrfutil) from PyPi
-    git clone https://github.com/adafruit/Adafruit_nRF52_Arduino.git
+
-    cd Adafruit_nRF52_Arduino/tools/nrfutil-0.5.2/
+    $ pip3 install adafruit-nrfutil --user
-    sudo pip install -r requirements.txt
-    sudo python setup.py install
 
 **make flash** and **make sd** will not work with DFU targets. Hence, **dfu-gen** and **dfu-flash** must be used instead.
 * dfu-gen: Generates a Firmware zip to be used by the DFU flash application.
@@ -111,8 +110,7 @@ note: On Linux it might be required to link SEGGER's `libjlinkarm.so` inside nrf
 Example on how to generate and flash feather52832 target:
 
     make BOARD=feather52832 SD=s132
-    make BOARD=feather52832 SD=s132 dfu-gen
+    make BOARD=feather52832 SD=s132 dfu-gen dfu-flash
-    make BOARD=feather52832 SD=s132 dfu-flash
 
 ## Bluetooth LE REPL
 

ports/nrf/boards/feather52832/README.md

@@ -21,24 +21,15 @@ $ cd ports/nrf
 $ ./drivers/bluetooth/download_ble_stack.sh
 ```
 
-## Installing `nrfutil`
+## Installing `adafruit-nrfutil`
 
 The Adafruit Bluefruit nRF52 Feather ships with a serial and OTA BLE bootloader
 that can be used to flash firmware images over a simple serial connection,
 using the on-board USB serial converter.
 
-If you haven't installed this command-line tool yet, go to the `/libs/nrfutil`
+run follow command to install [adafruit-nrfutil](https://github.com/adafruit/Adafruit_nRF52_nrfutil) from PyPi
-folder (where nrfutil 0.5.2 is installed as a sub-module) and run the following
-commands:
 
-> If you get a 'sudo: pip: command not found' error running 'sudo pip install',
+    $ pip3 install adafruit-nrfutil --user
-you can install pip via 'sudo easy_install pip'
-
-```
-$ cd ../../lib/nrfutil
-$ sudo pip install -r requirements.txt
-$ sudo python setup.py install
-```
 
 # Building and flashing firmware images
 
@@ -75,7 +66,7 @@ You can then connect over BLE UART using an application like Bluefruit LE
 Connect, available for Android, iOS and OS X, or any other application that
 supports the NUS service and allows you to send the corrent EOL sequence.
 
-## Flashing binaries with `nrfutil`
+## Flashing binaries with `adafruit-nrfutil`
 
 ### 1. **Update bootloader** to single-bank version
 
@@ -90,20 +81,25 @@ Due to the size of CircuitPython, we must migrate this bootloader to a
 bootloader from the dual-bank version that ships on Arduino-based Adafruit
 Feather52 boards to a single-bank CircuitPython compatible version:
 
+Firstly clone the [Adafruit_nRF52_Bootloader](https://github.com/adafruit/Adafruit_nRF52_Bootloader.git) and enter its directory
+
+	$ git clone https://github.com/adafruit/Adafruit_nRF52_Bootloader.git
+    $ cd Adafruit_nRF52_Bootloader
+
 #### S132 v2.0.1 single-bank (recommended):
 
-By default s132 v2.0.1 is used when no `SOFTDEV_VERSION` field is passed in:
+To flash bootloader with s132 v2.0.1
 
 ```
-$ make BOARD=feather52832 SERIAL=/dev/tty.SLAB_USBtoUART boot-flash
+$ make BOARD=feather_nrf52832 VERSION=2.0.1 SERIAL=/dev/tty.SLAB_USBtoUART dfu-flash
 ```
 
 #### S132 v5.0.0 (BLE5, experimental):
 
-To enable BLE5 support and the latest S132 release, flash the v5.0.0 bootloader via:
+To flash bootloader with s132 v5.0.0
 
 ```
-$ make BOARD=feather52832 SERIAL=/dev/tty.SLAB_USBtoUART SOFTDEV_VERSION=5.0.0 boot-flash
+$ make BOARD=feather52832 VERSION=5.0.0 SERIAL=/dev/tty.SLAB_USBtoUART dfu-flash
 ```
 
 ### 2. Generate and flash a CircuitPython DFU .zip package over serial

ports/nrf/boards/feather52832/bootloader/.gitattributes

@@ -1,2 +0,0 @@
-# Inform git that .zip files should be treated as binary
-*.zip binary

ports/nrf/boards/feather52832/bootloader/README.md

@@ -1,9 +0,0 @@
-# Adafruit nRF52 Feather Single-Bank Bootloader
-
-These files contain an implementation of a single-bank bootloader,
-which doubles the amount of flash memory available to applications
-at the expense of safe over the air updates.
-
-Two versions are present, based on release **2.0.1** and **5.0.0**
-of the Nordic S132 SoftDevice. The SoftDevice is included as poart
-of the bootloader binary.

ports/nrf/boards/feather52840/README.md

@@ -43,7 +43,7 @@ update the core CircuitPython firmware and internal file system contents
 using only a serial connection.
 
 On empty devices, the serial bootloader will need to be flashed once using a
-HW debugger such as a Segger J-Link before the serial updater (`nrfutil`) can
+HW debugger such as a Segger J-Link before the serial updater (`adafruit-nrfutil`) can
 be used.
 
 ### Install `nrfjprog`
@@ -79,20 +79,27 @@ JLinkARM.dll version: 6.20f
 > This operation only needs to be done once, and only on boards that don't
   already have the serial bootloader installed.
 
+Firstly clone the [Adafruit_nRF52_Bootloader](https://github.com/adafruit/Adafruit_nRF52_Bootloader.git) and enter its directory
+
+```
+$ git clone https://github.com/adafruit/Adafruit_nRF52_Bootloader.git
+$ cd Adafruit_nRF52_Bootloader
+```
+
 Once `nrfjprog` is installed and available in `PATH` you can flash your
 board with the serial bootloader via the following command:
 
 ```
-make SD=s140 BOARD=feather52840 bootloader
+make BOARD=feather_nrf52840_express VERSION=latest flash
 ```
 
 This should give you the following (or very similar) output, and you will see
 a DFU blinky pattern on one of the board LEDs:
 
 ```
-$ make SD=s140 BOARD=feather52840 bootloader
+$ make BOARD=pca10056 VERSION=latest flash
-Use make V=1, make V=2 or set BUILD_VERBOSE similarly in your environment to increase build verbosity.
+Flashing: bin/pca10056/6.0.0r0/pca10056_bootloader_s140_6.0.0r0.hex
-nrfjprog --program boards/feather52840/bootloader/feather52840_bootloader_6.0.0_s140_single.hex -f nrf52 --chiperase --reset
+nrfjprog  --program bin/pca10056/6.0.0r0/pca10056_bootloader_s140_6.0.0r0.hex --chiperase -f nrf52 --reset
 Parsing hex file.
 Erasing user available code and UICR flash areas.
 Applying system reset.
@@ -105,6 +112,8 @@ Run.
 From this point onward, you can now use a simple serial port for firmware
 updates.
 
+Note: You can specify other version that are available in the directory `Adafruit_nRF52_Bootloader/bin/feather_nrf52840_express/` . The `VERSION=latest` will use the latest bootloader available.
+
 ### IMPORTANT: Disable Mass Storage on PCA10056 J-Link
 
 The J-Link firmware on the PCA10056 implement USB Mass Storage, but this
@@ -135,31 +144,14 @@ J-Link>exit
 
 ## Building and Flashing CircuitPython
 
-### Installing `nrfutil`
+### Installing `adafruit-nrfutil`
 
-If you haven't installed the required command-line tool yet, go to the
+run follow command to install [adafruit-nrfutil](https://github.com/adafruit/Adafruit_nRF52_nrfutil) from PyPi
-`/libs/nrfutil` folder (where nrfutil 0.5.2b is installed as a sub-module)
-and run the following commands:
-
-> If you get a 'sudo: pip: command not found' error running 'sudo pip install',
-you can install pip via 'sudo easy_install pip'
 
 ```
-$ cd ../../lib/nrfutil
+$ pip3 install adafruit-nrfutil --user
-$ sudo pip install -r requirements.txt
-$ sudo python setup.py install
 ```
 
-#### Changes to `nrfutil` in 0.5.2d
-
-**IMPORTANT**: Make sure that you have version **0.5.2d**, since a small
-change was required to `dfu_transport_serial.py` to account for the
-increased minimum flash erase time on the nRF52840 compared to the earlier
-nRF52832!
-
-You can also manually change the file with the following new values (lines
-67-68), and reinstall the utility via `sudo python setup.py install`:
-
 ### Flashing CircuitPython with USB CDC
 
 With the serial bootloader present on your board, you first need to force your
@@ -169,8 +161,7 @@ BUTTON1 still pressed as you come out of reset).
 This will give you a **fast blinky DFU pattern** to indicate you are in DFU
 mode.
 
-At this point, you can **build and flash** a CircuitPython binary via the following
+you can **build and flash** a CircuitPython binary via the following command:
-command:
 
 ```
 $ make V=1 SD=s140 SERIAL=/dev/tty.usbmodem1411 BOARD=feather52840 all dfu-gen dfu-flash
@@ -197,19 +188,19 @@ Device programmed.
 
 ### Flashing CircuitPython with MSC UF2
 
-Make `uf2` target to generate the uf2
+uf2 file is generated at the end of `all` target
 
 ```
-$ make V=1 SD=s140 SERIAL=/dev/tty.usbmodem1411 BOARD=feather52840 all uf2
+$ make V=1 SD=s140 SERIAL=/dev/tty.usbmodem1411 BOARD=feather52840 all
 Create firmware.uf2
-../../tools/uf2/utils/uf2conv.py -c -o "build-feather52840-s140/firmware.uf2" "build-feather52840-s140/firmware.hex"
+../../tools/uf2/utils/uf2conv.py -f 0xADA52840 -c -o "build-feather52840-s140/firmware.uf2" "build-feather52840-s140/firmware.hex"
 Converting to uf2, output size: 392192, start address: 0x26000
 Wrote 392192 bytes to build-feather52840-s140/firmware.uf2.
 ```
 
 Simply drag and drop firmware.uf2 to the MSC, the nrf52840 will blink fast and reset after done.
 
-**Note**: you need to update `tools/uf2` for uf2conv.py to support hex file input, current circuitpython's master use older verion of uf2conv.py which only support biin file input. To update, change directory to top folder of circuitpython and run. The size of uf2 should be ~400KB, if using the old uf2conv.py the output file would be 1 MB which is not correct.
+**Note**: you need to update `tools/uf2` for uf2conv.py to support hex file input, current circuitpython's master use older verion of uf2conv.py which only support bin file input. To update, change directory to top folder of circuitpython and run. The size of uf2 should be ~400KB, if using the old uf2conv.py the output file would be 1 MB which is not correct.
 
 ```
 git submodule update --init