Robotis CM-900 as a tosser for Dynamixel commands

CM-900 is really tiny and cheap, so is perfect to use as communication bridge between any computer (Raspberry Pi, Pandaboard, etc. included, of course) and the Dynamixel bus. Whatever it receives from the Serial USB (usually commands and queries) is sent to the Dynamixel bus, and what it receives from the Dynamixel bus is sent to the SerialUSB (usually answers)

Here is the source code of the little program for CM-900 IDE:

[sourcecode language="C"]
int counter;
bool onlyOnceHappened;

void blinkOnce()
{
digitalWrite(BOARD_LED_PIN, LOW);
delay_us(100);
digitalWrite(BOARD_LED_PIN, HIGH);
}

void setup()
{
pinMode(BOARD_LED_PIN, OUTPUT);

onlyOnceHappened=false;
counter=0;

//USB Serial initialize
SerialUSB.begin();
// SerialUSB.attachInterrupt(USBDataReceived);
//DXL initialize
Dxl.begin(1);
}

byte aByte=0;
uint8 aUint8;

void loop()
{
// SerialUSB.println (counter++);

if (onlyOnceHappened==false)
{
blinkOnce();
onlyOnceHappened=true;
delay (3000); //Some time to the user to activate the monitor/console
SerialUSB.println ("v1.1.1 Orders receiver started");
}

if (SerialUSB.available())
{
aUint8=SerialUSB.read();
blinkOnce();
Dxl.writeRaw(aUint8);
// delay(20);
}

if (Dxl.available())
{
aByte=Dxl.readRaw();
blinkOnce();
SerialUSB.write(aByte);
// delay(20);
}
}

[/sourcecode]

Here the file.

In the next post I will include an improved version that could read sensors connected to the CM-900, "expanding" the Dynamixel protocol.