4-digit 7-segment displays are really neat little devices, it's a shame that they can be so cumbersome to control. Well that problem has been solved by making them a little bit 'smarter'. The 7-Segment Serial Display combines a classic 4-digit 7-segment display and an ATMega328 microcontroller allowing you to control every segment individually using only a few serial lines.
The Serial 7-Segment Display can be controlled in one of three ways: Serial TTL communication, SPI serial communication or I2C serial. You can even program it for stand-alone operation since the ATMega328 comes pre-loaded with the Arduino bootloader! There is also an FTDI header on board and we've provided a hardware profile for the Arduino IDE to make it even easier to program.
There's also been some layout changes to this design as well which will make it easier to incorporate these into your project. The power and I2C pins have been moved to the sides of the board such that you can chain them together in order to display longer strings of digits. There are also added mounting holes to the boards so you can mount them on standoffs (no more hot glue!)