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+# micro:bit BLE profile : Tracking changes from planned specification
+
+This document briefly outlines changes to the planned BLE specification made during implementation.
+These are typically made with purpose, so the rationale is also provided where possible.
+
+## LEDService:
+* Lose the System LED State characteristic since it cannot be controlled from the BLE MCU.
+* Lose the Scrolling State characteristic due to complexity and memory constraints.
+
+## IO Pin Service:
+* Simplify the IO Pin Service, possible to expose the edge connector pins only. 
+* Possibly drop it to save memory and use the event service to transport pin values in either direction. Needs further thought.
+
+## Generic Access Service: 
+* Device Name and Appearance are mandatory and so need values
+* Peripheral Privacy Flag is optional and I don’t think we need it. 
+* Ditto Reconnection Address.
+* Ditto Peripheral Preferred Connection Parameters.
+
+## Generic Attribute Service: 
+* profile design doc/report doesn’t show it and it’s mandatory (issue with Bluetooth Developer Studio). 
+
+## Device Information Service: 
+* All characteristics are optional. Which ones do we really want/need? Save a little memory.....
+
+