Example of how to use new Cross Device Download feature

Author: Stephen Schiffli

examples/anonymous_datasignals.js

@@ -0,0 +1,60 @@
+
+/**
+ * Created by sschiffli on 11/2/17.
+ */
+var MetaWear = require('../index')//require('metawear');
+
+// MetaWear.discoverByAddress('f6:3d:13:48:ce:ab', function (device) {
+MetaWear.discover(function (device) {
+  console.log('connecting...' + device.address);
+  device.connectAndSetUp(function (error) {
+    console.log('connected!');
+    MetaWear.mbl_mw_metawearboard_create_anonymous_datasignals(device.board,
+      MetaWear.FnVoid_MetaWearBoardP_AnonymousDataSignalP_UInt.toPointer(function (board, anonymousSignals, size) {
+        if (!anonymousSignals) {
+          console.log('nothing being logged');        
+          process.exit(1);
+        }
+        // Set the size on the array so we can index
+        anonymousSignals.length = size;
+        var i;
+        for (i = 0; i < size; i++) {
+          var identifier = MetaWear.mbl_mw_anonymous_datasignal_get_identifier(anonymousSignals[i]);
+          MetaWear.mbl_mw_anonymous_datasignal_subscribe(anonymousSignals[i], MetaWear.FnVoid_DataP.toPointer(function onSignal(dataPtr) {
+            var data = dataPtr.deref();
+            var pt = data.parseValue();
+            console.log(identifier + ':' + data.epoch + ' ' + JSON.stringify(pt));
+          }));
+        }
+        download(device, function () {
+          device.once('disconnect', function (reason) {
+            process.exit(0);
+          });
+          MetaWear.mbl_mw_macro_erase_all(device.board);
+          MetaWear.mbl_mw_debug_reset_after_gc(device.board);
+          MetaWear.mbl_mw_debug_disconnect(device.board);
+        });
+      }));
+  });
+});
+
+function download(device, callback) {
+  // Setup the handlers for events during the download
+  var downloadHandler = new MetaWear.LogDownloadHandler();
+  downloadHandler.received_progress_update = MetaWear.FnVoid_UInt_UInt.toPointer(function onSignal(entriesLeft, totalEntries) {
+    console.log('received_progress_update entriesLeft:' + entriesLeft + ' totalEntries:' + totalEntries);
+    if (entriesLeft === 0) {
+      callback(null);
+    }
+  });
+  downloadHandler.received_unknown_entry = MetaWear.FnVoid_UByte_Long_UByteP_UByte.toPointer(function onSignal(id, epoch, data, length) {
+    console.log('received_unknown_entry');
+  });
+  downloadHandler.received_unhandled_entry = MetaWear.FnVoid_DataP.toPointer(function onSignal(dataPtr) {
+    var data = dataPtr.deref();
+    var dataPoint = data.parseValue();
+    console.log('received_unhandled_entry: ' + dataPoint);
+  });
+  // Actually start the log download, this will cause all the handlers we setup to be invoked
+  MetaWear.mbl_mw_logging_download(device.board, 20, downloadHandler.ref());
+}