X-Git-Url: http://git.linex4red.de/pub/lufa.git/blobdiff_plain/de9d05f32a8f6ea8e10f601bcbb0bcbcea0975d1..refs/heads/master:/Bootloaders/CDC/BootloaderCDC.txt

diff --git a/Bootloaders/CDC/BootloaderCDC.txt b/Bootloaders/CDC/BootloaderCDC.txt
index 29bfd78f3..f8c349cde 100644
--- a/Bootloaders/CDC/BootloaderCDC.txt
+++ b/Bootloaders/CDC/BootloaderCDC.txt
@@ -54,6 +54,33 @@
  *  When the bootloader is running, the board's LED(s) will flash at regular intervals to distinguish the
  *  bootloader from the normal user application.
  *
+ *  \warning <b>THIS BOOTLOADER IS NOT SECURE.</b> Malicious entities can recover written data, even if the device
+ *           lockbits are set.
+ *
+ *  \section Sec_Running Running the Bootloader
+ *
+ *  On the USB AVR8 devices, setting the \c HWBE device fuse will cause the bootloader to run if the \c HWB pin of
+ *  the AVR is grounded when the device is reset.
+ *
+ *  The are two behaviours of this bootloader, depending on the device's fuses:
+ *
+ *  <b>If the device's BOOTRST fuse is set</b>, the bootloader will run any time the system is reset from
+ *  the external reset pin, unless no valid user application has been loaded. To initiate the bootloader, the
+ *  device's external reset pin should be grounded momentarily.
+ *
+ *  <b>If the device's BOOTRST fuse is not set</b>, the bootloader will run only if initiated via a software
+ *  jump, or if the \c HWB pin was low during the last device reset (if the \c HWBE fuse is set).
+ *
+ *  For board specific exceptions to the above, see below.
+ *
+ *  \subsection SSec_XPLAIN Atmel Xplain Board
+ *  Ground the USB AVR JTAG's \c TCK pin to ground when powering on the board to start the bootloader. This assumes the
+ *  \c HWBE fuse is cleared and the \c BOOTRST fuse is set as the HWBE pin is not user accessible on this board.
+ *
+ *  \subsection SSec_Leonardo Arduino Leonardo Board
+ *  Ground \c IO13 when powering the board to start the bootloader. This assumes the \c HWBE fuse is cleared and the
+ *  \c BOOTRST fuse is set as the HWBE pin is not user accessible on this board.
+ *
  *  \section Sec_Installation Driver Installation
  *
  *  After running this bootloader for the first time on a new computer, you will need to supply the .INF
@@ -117,6 +144,12 @@
  *  #define BOOTLOADER_ADDRESS_LENGTH          4
  *  \endcode
  *
+ *  From the application the API support of the bootloader can be detected by reading the FLASH memory bytes located at address
+ *  \c BOOTLOADER_MAGIC_SIGNATURE_START and comparing them to the value \c BOOTLOADER_MAGIC_SIGNATURE. The class of bootloader
+ *  can be determined by reading the FLASH memory bytes located at address \c BOOTLOADER_CLASS_SIGNATURE_START and comparing them
+ *  to the value \c BOOTLOADER_CDC_SIGNATURE. The start address of the bootloader can be retrieved by reading the bytes of FLASH
+ *  memory starting from address \c BOOTLOADER_ADDRESS_START.
+ *
  *  \subsection SSec_API_MemLayout Device Memory Map
  *  The following illustration indicates the final memory map of the device when loaded with the bootloader.
  *
@@ -155,11 +188,21 @@
  *  +----------------------------+ FLASHEND
  *  \endverbatim
  *
- *  Bootloaders reporting a device release revision number of 1.00 or greater are bootloader API enabled. From the application
- *  the API support of the bootloader can be detected by reading the FLASH memory bytes located at address \c BOOTLOADER_MAGIC_SIGNATURE_START
- *  and comparing them to the value \c BOOTLOADER_MAGIC_SIGNATURE. The class of bootloader can be determined by reading the
- *  FLASH memory bytes located at address \c BOOTLOADER_CLASS_SIGNATURE_START and comparing them to the value \c BOOTLOADER_CDC_SIGNATURE.
- *  The start address of the bootloader can be retrieved by reading the bytes of FLASH memory starting from address \c BOOTLOADER_ADDRESS_START.
+ *  \section Sec_KnownIssues Known Issues:
+ *
+ *  \par On Linux machines, the CDC bootloader is unstable or inaccessible.
+ *  A change to the \c ModemManager module in many Linux distributions causes
+ *  this module to try to take control over inserted CDC devices, corrupting the
+ *  datastream. A UDEV rule is required to prevent this.
+ *  See <a href=https://groups.google.com/d/msg/lufa-support/CP9cy2bc8yo/kBqsOu-RBeMJ>here</a> for resolution steps.
+ *  If the issue still persists then uninstall modemmanager by executing <tt>sudo apt-get remove modemmanager</tt>, or
+ *  the equivalent using your chosen distribution's package manager.
+ *
+ *  \par On Linux machines, the CDC bootloader is inaccessible.
+ *  On many Linux systems, non-root users do not have automatic access to newly
+ *  inserted CDC devices. Root privileges or a UDEV rule is required to gain
+ *  access.
+ *  See <a href=https://groups.google.com/d/msg/lufa-support/CP9cy2bc8yo/kBqsOu-RBeMJ>here</a> for resolution steps.
  *
  *  \section Sec_Options Project Options
  *
@@ -167,9 +210,9 @@
  *
  *  <table>
  *   <tr>
- *    <td><b>Define Name:</b></td>
- *    <td><b>Location:</b></td>
- *    <td><b>Description:</b></td>
+ *    <th><b>Define Name:</b></th>
+ *    <th><b>Location:</b></th>
+ *    <th><b>Description:</b></th>
  *   </tr>
  *   <tr>
  *    <td>NO_BLOCK_SUPPORT</td>