Usb serial (#1648)

* enabled usb clock
* added usb stack to application
* fixed pll0usb clock setup
* implemented serial usb handshake
* implemented serial communication
* integrated chibios shell
* implemented device reset
* implemented enter dfu mode
* implemented hackrf mode command
* implemented flash command
* implemented memory manipulation
* implemented button control
* fixed mode change
* improved reset behavior
* implemented directory commands
* implemented file commands
* improved data communication
* refactorings

firmware/tools/copy_external_apps.sh

@@ -26,6 +26,15 @@
 try=1
 while [ $try -le 180 ]
 do
+    if [ -c /dev/ttyACM0 ];
+    then
+        echo "" > /dev/ttyACM0
+        sleep 1
+        echo "sd_over_usb" > /dev/ttyACM0
+        sleep 5
+    fi
+
+
     if ls /dev/disk/by-id/*Portapack*part1 1> /dev/null 2>&1; then
         disk=$(ls /dev/disk/by-id/*Portapack*part1)
         part=$(readlink -f $disk)

firmware/tools/enter_mode.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+#
+# Copyright (C) 2023 Bernd Herzog
+#
+# This file is part of PortaPack.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+#
+
+# This script will copy compiled external apps to the Portapack.
+
+mode=$1
+
+echo "entering mode $mode"
+
+if [ -c /dev/ttyACM0 ];
+then
+    echo "" > /dev/ttyACM0
+    sleep 1
+    echo "$mode" > /dev/ttyACM0
+fi