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); }