Add simple mbed-enabled documentation entry

README.md

@@ -12,6 +12,8 @@
 * [mbedls as command line tool](#mbedls-as-command-line-tool)
   * [Exporting mbedls output to JSON](#exporting-mbedls-output-to-json)
 * [Porting instructions](#porting-instructions)
+  * [mbed-enabled technical specification overview](#mbed-enabled-technical-specification-overview)
+    * [TargetID as device unique identifier](#targetid-as-device-unique-identifier)
   * [mbed-ls auto-detection approach for Ubuntu](#mbed-ls-auto-detection-approach-for-ubuntu)
 * [Retarget mbed-ls autodetection results](#retarget-mbed-ls-autodetection-results)
   * [mbedls.json file properties](#mbedlsjson-file-properties)
@@ -231,6 +233,48 @@ You can help us improve the mbed-ls tools by - for example - committing a new OS
 
 For further study please check how Mac OS X (Darwin) was ported in [this pull request](https://github.com/ARMmbed/mbed-ls/pull/1).
 
+## mbed-enabled technical specification overview
+
+[mbed-enabled](https://www.mbed.com/en/about-mbed/mbed-enabled/) program is designed for mbed developers and partners who want to clearly identify their products as interoperable mbed Enabled technologies.
+User facing [DAPLink](https://github.com/mbedmicro/DAPLink#daplink) interface connects mbed-enabled device with host computer using USB interface.
+
+Interface chip should in general follow few generic rules to allow proper host detection and compliance with for example mbed test tools. There are listed below:
+* Existance of CDC (virtual serial port)
+  * Must support at all standard baudrates 9600 thru 115200
+  * Must Support `SendBreak` resulting in target reset sequence
+  * MUst have TargetID embedded in USBID
+* Mass Storage Device Class
+  * Must support programming binary files (copy file on MSD results in target flashing)
+  * Target flashing should not result in automatic target reset
+  * Must have `DETAILS.TXT` with DAPlink specification
+  * Must have `mbed.htm` with DAPlink specification
+  * `mbed.htm` should contain link to platform with `TargetID` specified
+  * Must have TargetID embedded in `USBID`
+
+### TargetID as device unique identifier
+
+Each device must have an unique identifier which generic format is specified in below chapter.
+
+TargetID generic format:
+* ASCII string containing hexadecimal values only: `[a-fA-F0-9]{4, }`
+* Should be longer than four ASCII characters (two bytes of hex data)
+* First 2 bytes coded with four ASCII characters are `vendor code`
+    * Note: *There might be more than one vendor code value assigned to one vendor.*
+* Following 2 bytes coded with four ASCII characters are `platform code`*
+* Rest of ASCII characters are vendor / platform specific. Ignored by mbed-enabled tools
+* `Vendor code` + `platform code` should create globally unique value
+
+Example TargetID coding:
+* Freescale `K64F` TargetID: `0240000033514e450019500585d40008e981000097969900`
+
+```
+        02	40	000033514e450019500585d40008e981000097969900
+        |   |
+        |   v
+        v	K64F
+        Freescale
+```
+
 ## mbed-ls auto-detection approach for Ubuntu
 
 Let's connect a few mbed boards to our Ubuntu host. The devices should mount as MSC and CDC (virtual disk and serial port). We'll use regular Linux commands to see the boards, then see how ```mbed-ls``` displays them.