The nootropic design Video Experimenter shield uses some pretty advanced features of the Arduino’s ATmega328 microcontroller. One downside of this is that you can’t use the Video Experimenter shield on an Arduino Mega. Why? Well, the designers of the Arduino Mega didn’t connect a lot of the ATmega1280/ATmega2560 pins to headers on the board so that you could use them! And, as it turns out, the pins with key features utilized by the Video Experimenter are not connected to anything!
To perform video overlay, the Video Experimenter relies on an input capture pin (to capture the exact time that the pin has changed state). Even though the ATmega1280/ATmega2560 has 4 input capture pins, none of them are connected!
And to capture video images in the Arduino’s memory, Video Experimenter uses the analog comparator in the chip. But the AIN0 pin for the analog comparator is not connected! What were the Arduino Mega designers thinking?
Fortunately, there is the Seeeduino Mega. The guys at Seeed Studio broke out nearly all the pins on the ATmega1280 so that you can use them. I love the Seeeduino Mega because it provides so many pins on a rather small board.
Simply make 5 connections with jumper wires and you can use the Video Experimenter on the Seeeduino Mega. No code changes necessary!
Here are the connections to make:
11 to 9 (white wire in picture above)
7 to 29 on the Seeeduino Mega (yellow wire)
INPUT pin on the Video Experimenter to PE2 on the Seeeduino Mega (green wire)
SYNCOUT pin on the Video Experimenter to PD4 on the Seeeduino Mega (gray wire)
VSYNC pin on the Video Experimenter to 21 on the Seeeduino Mega (brown wire)
Now you can use the Video Experimenter with an Arduino that has a more powerful processor. It really helps to have 8K of SRAM instead of 2K. Now you can do text and graphics overlay with higher resolutions, like 192×128. Have fun!