[cctalk] Re: Good computer books for 1960's computers

That depends. One answer is "all of them" -- because any general purpose computer can do both. If you meant "had machine instructions both for decimal and for binary arithmetic", the answer includes the PDP-11 and VAX, and I think the Intel 4004 had instructions used as building blocks in decimal arithmetic. By the way, on the subject of good books, Bell & Newell, "Computer structures: readings and examples" is very good. It categorizes computers a number of different ways, and covers a range of examples touching on most of the categories. The Google search mentions an authorized online copy at Gordon Bell's website: https://gordonbell.azurewebsites.net/cgb%20files/computer%20structures%20re… And here is the table of contents: https://ed-thelen.org/comp-hist/bell-71-t-o-c.html Apparently there is a second edition. I'm pretty sure I have the first edition. Lots of neat machines in there. Mainstream ones like the PDP-8 and IBM 360, stack machines (Burroughs 5500), vector processing (SIMD) machines (Illiac IV), and oddballs like the very early Dutch computer ZEBRA (a Dutch acronym for "extremely simple binary computer"). That one could be considered a microprogrammed machine where the horizontal microcode is what you use to write your applications. Since I learned about printing and typesetting at one point, I found it fascinating that this book comes in an unusual format: it is only one of two books I have ever seen that is square (the other being "Powers of ten" -- wonderful also). paul