add examples of IO reading and writing

epics-extensions · Mar 6, 2019 · 25e1fea · 25e1fea
1 parent 294a4c4
commit 25e1fea
Showing 1 changed file with 39 additions and 3 deletions.
diff --git a/snippets/c.json b/snippets/c.json
@@ -8,10 +8,46 @@
 
     "aSub Record C subroutine": {
         "prefix": "asub_code",
-        "body": [   "static long ${1:my_asub_routine}(aSubRecord *precord){",
-                    "    ${2:// insert code here}",
+        "body": [   "// most of these examples are coming from Yves Lussignol (https://drf-gitlab.cea.fr/, signalProcessingApp module)",
+                    "// the goal is to provide examples of reading and writing in different variable types",
+                    "static long ${1:my_asub_routine}(aSubRecord *precord){",
+                    "    // inputs:",
+                    "    //     - a: short",
+                    "    //     - b: float[]",
+                    "    //     - c: int",
+                    "    // outputs:",
+                    "    //     - vala: float",
+                    "    //     - valb: float[]",                    
+                    "    ",
+                    "    // inputs",
+                    "    short inputA = *(short *)precord->a;                     // input scalar",
+                    "    epicsFloat32 *inputB_array = (epicsFloat32 *)precord->b; // input array",   
+                    "    int nob      = precord->nob                              // nb of element in array (input b)",
+                    "    int inputC   = *(epicsUInt32 *)precord->c;",
+                    "    ",
+                    "    // read the whole input array (input b)",
+                    "    float val;",
+                    "    for (int i=0; i<nbOfElement; i++) {",
+                    "        val = *inputB_array++;",
+                    "    // read cell 3 of input array (input b)",
+                    "    val = inputB_array[2];    // <=> val = ((epicsFloat32 *)precord->b)[2];",
+                    "    ",
+                    "    // write the whole output array (output b)",
+                    "    epicsFloat32 *outputB_array = (epicsFloat32 *)precord->valb;",
+                    "    for(int i=0; i < nbOfElement; i++){",
+                    "        *outputB_array++ = i;",
+                    "    }",
+                    "    // write cell 3 of output array (ouput b)",
+                    "    outputB_array[2] = 3.14;    // <=> ((epicsFloat32 *)precord->valb)[2] = 3.10;",
+                    "    ",
+                    "    ${2:// insert your code here}",
+                    "    ",
+                    "    // outputs",
+                    "    *(float *)precord->vala = 94.77;",
+                    "    precord->nevb           = outsize; // number of output array elements",
+                    "    ",
                     "    return 0;",
                     "}",
                     "epicsRegisterFunction(${1:my_asub_routine});"]
     }
-}
+}