Updated FAQ (markdown)

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@@ -106,21 +106,50 @@ http://arduino.cc/en/uploads/Main/arduino-micro-schematic.pdf
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 ## Bootloader jump doesn't work\r
-Properly configure boot section size in Makefile. With wrong section size bootloader won't probably start with **Magic command** and **Boot Magic**.\r
-- https://github.com/tmk/tmk_keyboard#magic-commands\r
-- https://github.com/tmk/tmk_keyboard#bootloader\r
-\r
+Properly configure bootloader size in Makefile. With wrong section size bootloader won't probably start with **Magic command** and **Boot Magic**.\r
 ```\r
-# Boot Section Size in *bytes*\r
-#   Teensy halfKay   512\r
-#   Teensy++ halfKay 1024\r
-#   Atmel DFU loader 4096       (TMK Alt Controller)\r
-#   LUFA bootloader  4096\r
-#   USBaspLoader     2048\r
+# Size of Bootloaders in bytes:\r
+#   Atmel DFU loader(ATmega32U4)   4096    \r
+#   Atmel DFU loader(AT90USB128)   8192    \r
+#   LUFA bootloader(ATmega32U4)    4096             \r
+#   Arduino Caterina(ATmega32U4)   4096             \r
+#   USBaspLoader(ATmega***)        2048             \r
+#   Teensy   halfKay(ATmega32U4)   512              \r
+#   Teensy++ halfKay(AT90USB128)   1024\r
 OPT_DEFS += -DBOOTLOADER_SIZE=4096\r
 ```\r
+AVR Boot section size are defined by setting **BOOTSZ** fuse in fact. Consult with your MCU datasheet.\r
+Note that **Word**(2 bytes) size and address are used in datasheet while TMK uses **Byte**.\r
+\r
+AVR Boot section is located at end of Flash memory like the followings.\r
+```\r
+byte     Atmel/LUFA(ATMega32u4)          byte     Atmel(AT90SUB1286)\r
+0x0000   +---------------+               0x00000  +---------------+\r
+         |               |                        |               |\r
+         |               |                        |               |\r
+         |  Application  |                        |  Application  |\r
+         |               |                        |               | \r
+         =               =                        =               =\r
+         |               | 32KB-4KB               |               | 128KB-8KB\r
+0x6000   +---------------+               0x1FC00  +---------------+\r
+         |  Bootloader   | 4KB                    |  Bootloader   | 8KB\r
+0x7FFF   +---------------+               0x1FFFF  +---------------+\r
+\r
+ \r
+byte     Teensy(ATMega32u4)              byte     Teensy++(AT90SUB1286)\r
+0x0000   +---------------+               0x00000  +---------------+\r
+         |               |                        |               |\r
+         |               |                        |               |\r
+         |  Application  |                        |  Application  |\r
+         |               |                        |               |\r
+         =               =                        =               =\r
+         |               | 32KB-512B              |               | 128KB-1KB\r
+0x7E00   +---------------+               0x1FC00  +---------------+\r
+         |  Bootloader   | 512B                   |  Bootloader   | 1KB\r
+0x7FFF   +---------------+               0x1FFFF  +---------------+\r
+```\r
 \r
-And see this discussion.\r
+And see this discussion for further reference.\r
 https://github.com/tmk/tmk_keyboard/issues/179\r
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