I retired from teaching in 2004, allowing me the time to write two books. Both books started as online versions. I have rewritten both books for No Starch Press. These extensively updated versions are available as paperbacks and in PDF, Mobi, and ePub formats.

• Introduction to Computer Organization: An Under the Hood Look at Hardware and A64 Assembly.

  If you have a Raspberry Pi 4, be sure to check out the RPi4 gpio section on your left.

  

  The superseded edition can only be used online, and I no longer maintain it. Also, it uses the 32-bit ARM instruction set, AArch32.

• Introduction to Computer Organization: An Under the Hood Look at Hardware and x86-64 Assembly.

  

  The superseded edition can only be used online, and I no longer maintain it.

I welcome any comments you have about the content, especially any errors that your find.

I maintain resources — corrections, program code, exercise solutions, and hints — for you to use with both versions of the books on GitHub.

Although I no longer maintain an office on campus, please feel free to email me.

If you are an instructor using either of these books, and would like to communicate with other instructors who are using the same book, please send me email, and I will connect you. Please include a way that I can verify that you are an instructor, for example, a link to your school homepage.