Serial: Add basic tests for throughput and latency

java/libraries/serial/test/serial_latency/arduino/serial_latency.ino

@@ -0,0 +1,12 @@
+void setup() {
+  Serial.begin(115200);
+}
+
+void loop() {
+  while (true) {
+    int in = Serial.read();
+    if (in != -1) {
+      Serial.write(in);
+    }
+  }
+}

java/libraries/serial/test/serial_latency/serial_latency.pde

@@ -0,0 +1,53 @@
+// Arduino Duemilanove (168) on OS X 10.9
+// with either 115200 or 38400 bps
+// on Processing 2.0.3 (cu & tty): 24 ms avg, 35 ms max
+// on Processing 2.1b1 (cu & tty): 18 ms avg, 35 ms max
+
+import processing.serial.*;
+Serial serial;
+int start;
+byte out = '@';
+int last_send = 0;
+byte[] in = new byte[32768];
+long num_fail = 0;
+long num_recv = 0;
+int max_latency = 0;
+
+void setup() {  
+  println(serial.list());
+  // change this accordingly
+  serial = new Serial(this, serial.list()[0], 115200);
+  start = millis();
+}
+
+void draw() {
+  background(255);
+  if (0 < serial.available()) {
+    int recv = serial.readBytes(in);
+    for (int i=0; i < recv; i++) {
+      if (in[i] == out) {
+        num_recv++;
+        int now = millis();
+        if (max_latency < now-last_send) {
+          max_latency = now-last_send;
+        }
+        last_send = 0;
+      }
+    }
+  }
+  if (last_send != 0 && 1000 < millis()-last_send) {
+    num_fail++;
+    last_send = 0;
+    println(num_fail+" bytes timed out");
+  }
+  if (last_send == 0) {
+    if (out == 'Z') {
+      out = '@';
+    }
+    serial.write(++out);
+    last_send = millis();
+  }
+  fill(0);
+  text(((millis()-start)/(float)num_recv+" ms avg"), 0, height/2);
+  text(max_latency+" ms max", 0, height/2+20);
+}

java/libraries/serial/test/serial_throughput/arduino/serial_thoughput.ino

@@ -0,0 +1,9 @@
+void setup() {
+  Serial.begin(115200);
+}
+
+void loop() {
+  while (true) {
+    Serial.write('.');
+  }
+}

java/libraries/serial/test/serial_throughput/serial_throughput.pde

@@ -0,0 +1,32 @@
+import processing.serial.*;
+Serial serial;
+int start;
+byte[] in = new byte[32768];
+long num_ok = 0;
+long num_fail = 0;
+long num_recv = 0;
+
+void setup() {
+  println(serial.list());
+  // change this accordingly
+  serial = new Serial(this, serial.list()[0], 115200);
+  start = millis();
+}
+
+void draw() {
+  background(255);
+  if (0 < serial.available()) {
+    int recv = serial.readBytes(in);
+    for (int i=0; i < recv; i++) {
+      if (in[i] == '.') {
+        num_ok++;
+      } else {
+        num_fail++;
+        println("Received "+num_fail+" unexpected bytes");
+      }
+      num_recv++;
+    }
+  }
+  fill(0);
+  text(num_recv/((millis()-start)/1000.0), 0, height/2);
+}