Every larger 68xx(x) system has a monitor program in Read Only Memory (ROM), and we have been supplying HUMBUG for those systems for years. As a bare minimum, a monitor should allow you to examine and change the contents of your computer's memory, and start a program. In fact, some monitors do only that! But HUMBUG is different. Not only can you start programs, you can also perform them just one step at a time, or you can insert breakpoints which let you perform entire sections of programs at a time. You can load and dump memory in various formats, including (on 6800 and 6809 systems) an instruction-by-instruction formatted display which lets you see and understand programs like never before. You can switch I/O devices on and off, fill and move memory, check memory and its contents, and more. And, as a special feature, the HUMBUG manual contains not just full instructions on its use, but a complete listing of HUMBUG as well. Examining this listing is educational in itself, since the best way to learn a new language is to see how other people use it.
The versions identified with * below are stock items; others are made to order after you specify your exact system configuration. (Before ordering one of the unstarred versions listed below, we suggest that you contact Star-K for information on versions and options available.)