Changes between Version 17 and Version 18 of ObjectDeveloperGuide

Timestamp:

11/28/09 14:06:57 (15 years ago)

Author:

ismael (IP: 62.57.1.15)

Comment:

--

ObjectDeveloperGuide

@@ -17 +17 @@
 
 ||'''Directory'''||'''Files'''||'''Comment'''||
+||''myobj''/platform_make/||...||One directory for each platform it can be compiled. For example:[[BR]]''lnx_make'' shall contain the Makefile, ''c6000_make'' shall contain CCS' .pjt files, etc.||
 ||''myobj''/interfaces/||inputs.h[[BR]]outputs.h[[BR]]stats.h||Definition of input/output interfaces, statistics variables and initialization parameters||
-||''myobj''/src/||myobj.c[[BR]]myobj_imp.c[[BR]]xxx.c||Implementation (myobj_imp.c + xxx.c) of the algorithm and main skeleton (myobj.c)[[BR]][[BR]]See below for more information||
+||''myobj''/src/||module.c[[BR]]module_imp.c[[BR]]myobj.c||myobj.c: Standalone function implementing the algorithm.[[BR]]module.c and module_imp.c is the skeleton[[BR]]See below for more information||
 ||''myobj''/bin/||myobj||Binaries after compilation and linking are placed here.||
 
@@ -65 +66 @@
 In order to facilitate objects programming an skeleton implementing some common functionalities has been defined. In this sense, the user will only have to define the interfaces in a constant structure and provide some functions to process data. The initialization and buffer management will be done by the skeleton.
 
-This skeleton is provided in the myobj.c file and is exactly the same for any object (so you can copy anyone provided by the example objects). The skeleton needs three header files: inputs.h, outputs.h and stats.h. Interfaces and statistics are defined in structures (defined in swapi_utils.h) which name has to be mantained (input_itfs, output_itfs, params and stats). The following figure describe these structures:
+This skeleton is provided in the module.c file and is exactly the same for any object (so you can copy anyone provided by the example objects). The skeleton needs three header files: inputs.h, outputs.h and stats.h. Interfaces and statistics are defined in structures (defined in swapi_utils.h) which name has to be mantained (input_itfs, output_itfs, params and stats). The following figure describe these structures:
 
 '''Figure 2 – Structure definitions (swapi_utils.h)'''
@@ -155 +156 @@
 
 }}}
-You can read more of how to use these structures in the example objects. If you downloaded the source, they are in the example directory.
-
-Finally, the following figure shows the file where the processing code should be written. Note that in the configuration of the structure we have provided a function to process (or generate) data for every interface. Now, the only thing we have to do is to code these functions:
-
-'''Figure 3 – Object implementation (myobj_imp.c)'''
+
+The other skeleton file, module_imp.c, is the bridge between the skeleton and the algorithm functions. It implements de functions called after a packet is received or must be generated. Although the algorithm could be implemented here, good coding practices recommend to do it in another file so the implementation shall be used in other contexts.
+
+'''Figure 3 – Object implementation (module_imp.c)'''
 
 {{{
@@ -165 +165 @@
  */
 #include <phal_sw_api.h>
-#include <math.h>
 #include <swapi_utils.h>
 
 #include <phal_hw_api.h>
 #include <sys/resource.h>
-
-#define PI 3.1415
 
 #include "inputs.h"
@@ -199 +196 @@
 
         /* generate sinusoid */
+        generate_sinusoid(output_data,fsin,fsamp);
+
+        SetStatsValue(stat_signal, output_data, len);
+
+        return 1;
+}
+
+int InitCustom()
+{
+    return 1;
+}
+
+int RunCustom()
+{
+    return 1;
+}
+
+
+}}}
+The last two functions ({{{InitCustom()}}} and {{{RunCustom()}}}) have also to be defined. The {{{InitCustom}}} function is used to implement custom initialization routines not related with interface or statistics initialization. For example, if an object has to compute a set of filter coeficients given an initialization parameter, it can be done in this function. The skeleton will get the parameter(s) value if we define it in the specific structure. After that, the {{{InitCustom}}} function will be called and we will perform the computations. 
+
+Analogously, the {{{RunCustom}}} function might be useful to perform some background tasks not related directly with data processing (more formally, asyncrhonous with data flow). An example of this may be updating an internal state.
+
+Finally, the actual algorithm will be implemented in a standalone file, for example, myobj.c:
+{{{
+/** ALOE headers
+ */
+#include <phal_sw_api.h>
+#include <math.h>
+
+#define PI 3.1415
+
+void generate_sinusoid(int *output_data, float fsin, float fsamp)
+{
+        int i;
         for (i=0;i<len;i++) {
                 output_data[i] = (int) ((float) 1000.0*cosf((double) 2.0*PI*fsin*i/freq));
         }
-
-        SetStatsValue(stat_signal, output_data, len);
-
-        return 1;
-}
-
-int InitCustom()
-{
-    return 1;
-}
-
-int RunCustom()
-{
-    return 1;
-}
-
-
-}}}
-The last two functions ({{{InitCustom()}}} and {{{RunCustom()}}}) have also to be defined. The {{{InitCustom}}} function is used to implement custom initialization routines not related with interface or statistics initialization. For example, if an object has to compute a set of filter coeficients given an initialization parameter, it can be done in this function. The skeleton will get the parameter(s) value if we define it in the specific structure. After that, the {{{InitCustom}}} function will be called and we will perform the computations. 
-
-Analogously, the {{{RunCustom}}} function might be useful to perform some background tasks not related directly with data processing (more formally, asyncrhonous with data flow). An example of this may be updating an internal state.
+}
+}}}
 
 == Compiling and Linking ==
 Compiling an ALOE objects does not need any other consideration rather than linking with the ALOE SW Library and HW Library. Obviously, we have to pick the HW library of our system. Under linux, and once we have installed ALOE (binary or source), the libraries should appear at /usr/local/lib with the names libsw_api.a and libhw_api.a.
 
-If your prefer to use autoconf/automake tools the following attached files might be useful:
-
- * sample configure.in
- * sample Makefile.am
+If your prefer to use autoconf/automake tools you might find useful the example Makefile.am included in the sample modules shipped in the ALOE distribution (under lnx_make).
+
 
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