The 7-Segment Serial Display turns the thirteen pins necessary to control a 4-digit seven segment display into just one or three. The display will give you full control of all digits, decimal points, the colon and the apostrophe. At the heart of the display is an ATMega328 which controls all the serial communications and the 4-digit 7-segment display through an easy to use API. The Serial 7-Segment Display can be controlled in one of two ways: (1) serial TTL communication or (2) SPI serial communication. Regardless of which method you use to communicate with the display, the display is controlled with 4-byte packets and special 2-byte commands. Project description, more information and ordering can be found at https://www.sparkfun.com/products/9764 User's Manual: http://www.sparkfun.com/datasheets/Components/LED/7-Segment/SFE-0012-DS-7segmentSerial-v41.pdf Source Code: http://www.sparkfun.com/datasheets/Components/LED/7-Segment/Serial-7-Seg-v2.zip