Arduino Serial Monitor shows strange ASCII characters

Question

I connected an ArduiMU v3+ via a FTDI-cable to my Mac (OS X 10.10) (latest VC FTDI driver is installed and loaded).

Inside the Arduino-software the Serial Monitor (monitoring /dev/cu.usbserial-AJ038NZ3) shows a lot of weird ASCII characters. What could be the reason for this problem?

enter image description here

Here's part of the code I uploaded to the ArduiMu:

void setup() {
// Init Serial for use by Send.cpp and Receive.cpp
Serial.begin(115200);
}
void loop() {
 Receive::doTasks();
}
 void Send::flexSensorData() {
 char packet[64];
 int packetLength = 0;
 IntUnion intUnion;
 FlexSensors::read(); // read sensors before sending
#ifdef BINARY_PACKETS
 packet[packetLength++] = 'F';
 intUnion.intVal= (int)FlexSensors::channel[0];
 packet[packetLength++] = intUnion.msb;
 packet[packetLength++] = intUnion.lsb;
 intUnion.intVal= (int)FlexSensors::channel[1];
 packet[packetLength++] = intUnion.msb;
 packet[packetLength++] = intUnion.lsb;
 intUnion.intVal= (int)FlexSensors::channel[2];
 packet[packetLength++] = intUnion.msb;
 packet[packetLength++] = intUnion.lsb;
 intUnion.intVal= (int)FlexSensors::channel[3];
 packet[packetLength++] = intUnion.msb;
 packet[packetLength++] = intUnion.lsb;
 intUnion.intVal= (int)FlexSensors::channel[4];
 packet[packetLength++] = intUnion.msb;
 packet[packetLength++] = intUnion.lsb;
 intUnion.intVal= (int)FlexSensors::channel[5];
 packet[packetLength++] = intUnion.msb;
 packet[packetLength++] = intUnion.lsb;
 packet[packetLength++] = calcChecksum(packet, packetLength);
#else
 packet[packetLength++] = 'F';
 packet[packetLength++] = ',';
 IntValToChars(packet, &packetLength, (int)FlexSensors::channel[0]);
 packet[packetLength++] = ',';
 IntValToChars(packet, &packetLength, (int)FlexSensors::channel[1]);
 packet[packetLength++] = ',';
 IntValToChars(packet, &packetLength, (int)FlexSensors::channel[2]);
 packet[packetLength++] = ',';
 IntValToChars(packet, &packetLength, (int)FlexSensors::channel[3]);
 packet[packetLength++] = ',';
 IntValToChars(packet, &packetLength, (int)FlexSensors::channel[4]);
 packet[packetLength++] = ',';
 IntValToChars(packet, &packetLength, (int)FlexSensors::channel[5]);
 packet[packetLength++] = ',';
 IntValToChars(packet, &packetLength, calcChecksum(packet, packetLength));
 packet[packetLength++] = '\r';
#endif
 Serial.write((uint8_t*)packet, packetLength);
}

• Ignacio Vazquez-Abrams: You're sending non-ASCII data.
• Eugene Sh.: Or a wrong Baud rate is set.
• Edgar Bonet: This code is not sending anything through the serial port.
• Vladimir Cravero: As already said, you are sending binary data so what you receive is (probably) right. Try to send "Hello world" and see if it works.
• jfpoilpret: The code you posted is incomplete; there is no evidence here that Send::flexSensorData() is called. Also, since your code includes conditional compilation, you should indicate the value of BINARY_PACKETS so we don't try to guess it from your code...