To open the CC bridge box remove three screws from the base (one under the sticker). Note at this point assume you have invalidated any warranty. Remove the board – it should look like this.
Connectors (left to right), Power – 4.5-6V @ 500mA, Ethernet mag jack, Serial port (RJ10) pins left to right Rx,Tx,GND,3v3 – note the 3v3 is supplied via a 10 ohm resistor R11 (current limiter).
Bridge across jumper 1 to disable the Wiznet W5100 ethernet chip and using your favorite technique (I used a USBTiny from Adafruit) burn the Arduino bootloader onto the AVR. Note only power the board from one source – either 3v3 from the programming device or the on board power (leave the programmers power unconnected). There are several examples on the web of using an Arduino to program a bootloader – just be aware that signals will need to be 3v3. Note the board ID needs to be “Arduino Pro or Pro Mini (3.3V, 8 MHz) w/ ATmega328”
Once the bootloader is on the board it is possible to program it using the Arduino IDE.
I used a USB to TTL FTDI serial converter (a good one is from Sparkfun). Signal levels will be 3v3 so there is no issue there, just connect up GND, board RX to FTDI TX and board TX to FTDI RX. I cut up the cable supplied for this – Farnell supply suitable RJ10 plugs (as far as I can tell these match the dimensions of the supplied plug).
Note: there is no auto reset so you need to hit the reset button once the sketch has compiled – you may need to practice this several times before you get the timing right (I did). I pressed the button when the compiled size came up on the screen, counted to three and released it – seemed about the right time.
The first sketch I loaded is the example Ethernet server sketch. You need to make one simple alteration to this. Add the following lines at the beginning of the setup routine (as well as verify that the mac and IP address are OK for your system):
This code will enable the W5100 ethernet chip as Digital I/O 7 is connected directly to the W5100 reset line. This line is connected via a resistor to GND and so we need to pull it up to enable the device.
Once the sketch is loaded into the board you should be able to connect a RJ45 ethernet cable and access the page from your browser.
I also notice that the board contains pads for an I2C EEPROM chip – I don’t think mine will be vacant for long, I have a 128KByte FRAM chip that will fit nicely there..
A further improvement will be to add a Micro SD card interface, I will then have all the ingredients for a cheap web server to front end my home monitoring system.