Step 8: Assemble Electronics and Test
Now that you have all of your electronics assembled individually, it's time to connect all of your breakout boards to your Arduino, program it and see if it works, this is also a good time to put everything into the main arch assembly to see if there is enough space and also to find the best layout for each of the individual systems.
How you connect the breakout boards to the Arduino is really up to you, the code lets you change the pin assignment easily so this isn't a problem, the only restriction is the SPI pins used by the Ethernet Shield, which I think are pins 50 upwards.
Once all of the connections have been made, connect a power source and power the system up, if all is well then the four individual 8x8 matrices should flash in sequence and the start up message should be shown on the LCDs, you may need to adjust the back light brightness and LCD contrast settings to get the displays looking clear and sharp.
If all is well so far, connect the Ethernet Shield to your network and the Arduino should update the LCDs with information from the web service, if this does not work, you should try connecting a PC via the same Ethernet connection and try to make a call to the web service, if this works then there may be a problem with the Arduino or Ethernet Shield, connecting the Arduino to your PC and looking at the serial messages being sent from the Arduino may help to find the problem in this case.
Now, if this part works try pressing the blue button to access the menu, this should be displayed on the 20x4 LCD. From here there are three options; close the menu, refresh the news and weather data and switch to media mode, selecting this option should clear the LCDs and turn on power to the amplifier modules, the 40x2 LCD should then update with the current song being played on Last.fm.
Pressing the blue button again should show the audio menu, from which the active input can be changed and the song data can be updated from Last.fm, there is no auto update feature for Last.fm as it interrupts the visualisation as it updates, switching the active input should toggle the signal select relay and Bluetooth power relay, during this time the LED matrix should also show a visualisation based on the magnitude of the active audio signal.
If everything works so far then it is a safe assumption that you have done everything right, this stage is a good time to add any other features you want.
Note: I thought I had more pictures of testing the electronics in the arch frame, but can't seem to find them, sorry about that.