Logic Calc: a design tool for digital systems

The author discusses the use of Logic Calc, a spreadsheet program that was developed for the design of digital systems. It provides a simple, interactive, highly visible, self-documenting method of designing digital systems at various levels of abstraction. Logic Calc allows the designer several capabilities not offered by financial spreadsheets, including an ability to specify the size in bits of each spreadsheet cell. This allows spreadsheet cells to closely represents registers, databuses, and other digital hardware of various sizes. Another specialized feature of Logic Calc is an ability to simulate registers and other key components of a digital system in a single spreadsheet cell