Prerequisite: If you haven't done it yet, download the Nand2Tetris Software Suite from the Software section of this website to your computer. Read Chapter 1 and Appendix 2 (not including A2.4), and go through parts I-II-III of the Hardware Simulator, before starting to work on this project.

Built-in chips: The Nand gate is considered primitive and thus there is no need to implement it: whenever a Nand chip-part is encountered in your HDL code, the simulator automatically invokes the built-in tools/builtInChips/Nand.hdl implementation. We recommend implementing all the other gates in this project in the order in which they appear in Chapter 1. However, note that the supplied hardware simulator features built-in implementations of all these chips. Therefore, you can use any one of these chips before implementing it: the simulator will automatically invoke their built-in versions.

For example, consider the supplied skeletal Mux.hdl program. Suppose that for one reason or another you did not complete the implementation of Mux, but you still want to use Mux chips as internal parts in other chip designs. You can easily do so, thanks to the following convention. If the simulator fails to find a Mux.hdl file in the current folder, it automatically invokes the built-in Mux implementation, which is part of the supplied simulator's environment. This built-in Mux implementation has the same interface and functionality as those of the Mux chip described in the book. Thus, if you want the simulator to ignore one or more of your chip implementations, rename the corresponding chiPname.hdl file, or remove it from the project folder. When you are ready to develop this chip in HDL, put the file chipName.hdl back in the folder, and proceed to edit it with your HDL code.

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