X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/18d91ece3b178a04d295518517b2aca5266bb078..31022dfbe9ba7f10e9be5be85e16d2ee203d40df:/Bootloaders/CDC/BootloaderCDC.txt

diff --git a/Bootloaders/CDC/BootloaderCDC.txt b/Bootloaders/CDC/BootloaderCDC.txt
index f5d5ddf99..337b6e4a5 100644
--- a/Bootloaders/CDC/BootloaderCDC.txt
+++ b/Bootloaders/CDC/BootloaderCDC.txt
@@ -54,6 +54,9 @@
  *  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_Installation Driver Installation
  *
  *  After running this bootloader for the first time on a new computer, you will need to supply the .INF
@@ -98,7 +101,7 @@
  *  #define BOOTLOADER_API_TABLE_SIZE          32
  *  #define BOOTLOADER_API_TABLE_START         ((FLASHEND + 1UL) - BOOTLOADER_API_TABLE_SIZE)
  *  #define BOOTLOADER_API_CALL(Index)         (void*)((BOOTLOADER_API_TABLE_START + (Index * 2)) / 2)
- *  
+ *
  *  void    (*BootloaderAPI_ErasePage)(uint32_t Address)               = BOOTLOADER_API_CALL(0);
  *  void    (*BootloaderAPI_WritePage)(uint32_t Address)               = BOOTLOADER_API_CALL(1);
  *  void    (*BootloaderAPI_FillWord)(uint32_t Address, uint16_t Word) = BOOTLOADER_API_CALL(2);
@@ -106,17 +109,23 @@
  *  uint8_t (*BootloaderAPI_ReadFuse)(uint16_t Address)                = BOOTLOADER_API_CALL(4);
  *  uint8_t (*BootloaderAPI_ReadLock)(void)                            = BOOTLOADER_API_CALL(5);
  *  void    (*BootloaderAPI_WriteLock)(uint8_t LockBits)               = BOOTLOADER_API_CALL(6);
- *  
+ *
  *  #define BOOTLOADER_MAGIC_SIGNATURE_START   (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 2))
  *  #define BOOTLOADER_MAGIC_SIGNATURE         0xDCFB
- *  
+ *
  *  #define BOOTLOADER_CLASS_SIGNATURE_START   (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 4))
- *  #define BOOTLOADER_CDC_SIGNATURE           0xCDC1
- *  
+ *  #define BOOTLOADER_CDC_SIGNATURE           0xDF00
+ *
  *  #define BOOTLOADER_ADDRESS_START           (BOOTLOADER_API_TABLE_START + (BOOTLOADER_API_TABLE_SIZE - 8))
  *  #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 +164,25 @@
  *  +----------------------------+ 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.
+ *
+ *  \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.
+ *
+ *  \par After loading an application, it is not run automatically on startup.
+ *  Some USB AVR boards ship with the BOOTRST fuse set, causing the bootloader
+ *  to run automatically when the device is reset. In most cases, the BOOTRST
+ *  fuse should be disabled and the HWBE fuse used instead to run the bootloader
+ *  when needed.
  *
  *  \section Sec_Options Project Options
  *
@@ -167,9 +190,9 @@
  *
  *  <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>