manual: added references to figures

docs/manual/markdown/docs/architecture.md

@@ -17,7 +17,7 @@ the architecture follows these fundamental design guidelines:
 -   *Statically bounded memory (optionally)* - The number of maximum
     connections/channels/services can be configured.
 
-Figure [below](#fig:BTstackArchitecture) shows the general architecture of a
+Figure {@fig:BTstackArchitecture} shows the general architecture of a
 BTstack-based single-threaded application that includes the BTstack run loop. 
 The Main Application contains the application logic, e.g., reading a sensor value and
 providing it via the Communication Logic as a SPP Server. The
@@ -28,7 +28,7 @@ for providing timers and processing incoming data.
 
 <a name="fig:BTstackArchitecture"></a> 
 
-![Architecture of a BTstack-based application.](picts/btstack-architecture.png)
+![Architecture of a BTstack-based application.](picts/btstack-architecture.png) {#fig:BTstackArchitecture}
 
 ## Single threaded design
 

docs/manual/markdown/docs/how_to.md

@@ -91,7 +91,7 @@ before its event handler callback is executed. If you need a periodic
 timer, you can re-register the same timer source in the callback
 function, as shown in Listing [PeriodicTimerHandler]. Note that BTstack
 expects to get called periodically to keep its time, see Section
-[section:timeAbstraction] for more on the tick hardware abstraction.
+[on time abstraction](#section:test) for more on the tick hardware abstraction.
 
 The run loop is set up by calling *run_loop_init* function for
 embedded systems:
@@ -111,7 +111,7 @@ communication over the UART.
 
 <a nam="sec:btstack_initialization"></a>
 
-## BTstack initialization
+## BTstack initialization {#section:test}
 
 To initialize BTstack you need to [initialize the memory](#section:memory_configuration)
 and [the run loop](#section:run_loop) respectively, then setup HCI and all needed higher

docs/manual/markdown/docs/integration.md

@@ -17,11 +17,10 @@ Communication Logic for its Bluetooth communication.
 
 
 In a single-threaded environment, all application components run on the
-same (single) thread and use direct function calls as shown in Figure [below](#fig:BTstackSingle).
+same (single) thread and use direct function calls as shown in
+Figure {@fig:BTstackSingle}.
 
-<a name="fig:BTstackSingle"></a>
-
-![BTstack in single-threaded environment](picts/singlethreading-btstack.png)
+![BTstack in single-threaded environment.](picts/singlethreading-btstack.png) {#fig:BTstackSingle}
 
 BTstack provides a basic run loop that supports the concept of data
 sources and timers, which can be registered centrally. This works well
@@ -57,16 +56,17 @@ common options:
 -   The Communication Logic is implemented on a dedicated BTstack
     thread, and the Main Application communicates with the BTstack
     thread via application-specific messages over an Interprocess
-    Communication (IPC). This option results in less code and quick 
-    adaption.
+    Communication (IPC) as depicted in Figure {@fig:MTMonolithic}. 
+    This option results in less code and quick adaption.
 
-    ![](picts/multithreading-monolithic.png)
+    ![BTstack in multi-threaded environment - monolithic solution.](picts/multithreading-monolithic.png) {#fig:MTMonolithic}
 
 -   BTstack must be extended to run standalone, i.e, as a Daemon, on a
     dedicated thread and the Main Application controls this daemon via
     BTstack extended HCI command over IPC - this is used for the
-    non-embedded version of BTstack e.g., on the iPhone. 
-    This option requires more code but provides more flexibility.
+    non-embedded version of BTstack e.g., on the iPhone and it is depicted 
+    in Figure {@fig:MTDaemon}. This option requires more code but provides 
+    more flexibility.
 
-    ![](picts/multithreading-btdaemon.png)
+    ![BTstack in multi-threaded environment - solution with daemon.](picts/multithreading-btdaemon.png) {#fig:MTDaemon}
     

docs/manual/markdown/docs/porting.md

@@ -1,7 +1,7 @@
 In this section, we highlight the BTstack components that need to be
 adjusted for different hardware platforms.
 
-<a name="sec:timeAbstraction"></a>
+<a name="section:timeAbstraction"></a>
 
 ## Time Abstraction Layer
 
@@ -11,9 +11,8 @@ system clock with millisecond resolution. BTstack’s timing requirements
 are quite low as only Bluetooth timeouts in the second range need to be
 handled.
 
-<a name="sec:tickAbstraction"></a>
 
-### Tick Hardware Abstraction 
+### Tick Hardware Abstraction ### {#section:tickAbstraction}
 
 
 If your platform doesn’t require a system clock or if you already have a

docs/manual/markdown/docs/protocols.md

@@ -34,12 +34,12 @@ between a peripheral and iOS device, the iAP1 and iAP2 protocols of the
 Made for iPhone program can be used instead of GATT. Please contact us
 directly for information on BTstack and MFi.
 
+Figure {@fig:BTstackProtocolArchitecture} depicts Bluetooth protocols
+and profiles that are currently implemented by BTstack.
 In the following, we first explain how the various Bluetooth protocols
-are used in BTstack. In the next chapter, we go over the profiles.
+are used in BTstack. In the next chapter, we go over the profiles. 
 
-<a name="fig:BTstackProtocolArchitecture"></a>
-
-![Architecture of a BTstack-based application.](picts/btstack-protocols.png)
+![Architecture of a BTstack-based application.](picts/btstack-protocols.png) {#fig:BTstackProtocolArchitecture}
 
 
 ## HCI - Host Controller Interface