I decided I wanted a good looking, fancy front panel for my Microtronic emulator. I designed a front panel blue print and tried to cut it out from plywood. I even acquired a used scroll saw, but I was unhappy with the result. I decided I wanted a more professional looking front panel, and was excited when I found the Custom Laser Cutting Service offered by Pololu Robitics and Electronics. All they required was the blueprint as a PDF, and 6 days later I had my transparent acrylic iced, fantastic looking front panel in the mail.

I mounted the big 20x4 LCD white-on-blue display as well as the two blue 7segment I2C-based LED backpacks (each with 4 digits) from Adafruit, and the 4x4 keypad. Since I was no longer using the LCD+keypad shield and had also lost the additional 8 buttons from the TM1638, I needed a lot of discrete N.O. pushbuttons, as well as LEDs (blue of course), and another 3x4 keypad for the function buttons.

Turns out that I would be using most of the Mega's IO pins now for wiring up all the buttons, LEDs, keypads, etc. An additional 4 pins were needed for the Microtronic's digital inputs, one more output pin for the 1 Hz clock signal, and so on. In the end, not many ports were left.

After I had wired up the front panel hardware, I simply used a wooden base board of matching dimensions, and hinges and L-brackets from Osh to create the triangular case you are seeing on these pages. The Arduino is mounted on the base board using screws. Hotglue was my friend, too. The case is easy to open up and this is still the only way to gain access to the SDCard in the SDCard+Ethernet shield (Ethernet is not used for anything currently btw).

The software had to revised significantly - after all, most of the hardware had changed, the only constant being the Mega 2560, the keypad, and some buttons. In order to drive two Adafruit LED backpacks of I2C I learned that the address of one of those had to be changed, by soldering a jumper. I also learned how to wire up the contrast potentiometer for the 4x2 Hitachi HD44780 LCD display. The contrast potentiometer was part of the LCD+keypad shield in the previous version, which I was no longer using.

Finally, Version 2 was working! At the end of Phase 2, Mega Emulator Version 2 looked as follows: