The original motivation behind our project was a desire to interface with some type of real world device. Since one of the clear limitations of the Atmel chipset is the lack of storage space, we felt it would be useful if we could connect to some type of mass media storage device. Implementing a SCSI interface would allow us to connect to virtually any type of storage device – hard drives, CD-ROM drives, and various removable media. Since Sean had a SCSI Zip drive lying around his apartment, our project concept began to come together.
However, we felt that connecting to a Zip drive wouldn’t do much by itself; we needed some data to store! After some research, we found that there were digital cameras that would connect through a serial port and had a simple programming interface. This was the perfect application of the Zip drive’s 100 MB storage capacity.
We have designed a board, using two of Atmel’s 90s8515 8-bit microcontrollers, that will retrieve a picture from a Barbie Cam and store that image onto a Zip drive with the press of a button. Additionally, our device can take stop-motion video and store the images in a numbered sequence of files. It is necessary to run these images through a Java program that will interpolate the raw pixel data into a readable bitmap file.
Although our project focuses on the Zip drive and Barbie camera, our project would also be able to handle data from any serial source and store it onto any type of SCSI-2 device with some minor code changes. A really neat feature of SCSI is that it’s totally backwards compatible, so any modern SCSI device can easily communicate as a single ended asynchronous device and thus interface with our board
For more detail: The Zip Drive