Oh data breakpoints! Our savior. In the bad old days Intel had a big 'blue box' that ran ISIS and had a $1200 cable and circuit board called 'ICE' for 'In-Circu

Oh data breakpoints! Our savior. In the bad old days Intel had a big 'blue box' that ran ISIS and had a $1200 cable and circuit board called 'ICE' for 'In-Circuit Emulator'. It could monitor the bus and trap on certain memory operations. My brother worked on that right out of college. He met his wife over that circuit board! Anyway fast forward a bit, I'm working at Convergent which was a nascent Intel's biggest single consumer of x86 chips. Intel was coming out with a shiny new version, the 80286, showed our engineers the spec. They complained "Hey! We're your biggest chip buyer but you didn't consult us on features!" Intel guy said "Ok, what features do you want?" Our folks said "We'll get back to you..." Then they circulated a questionnaire among us software types for ideas. I suggested "Let's get rid of that Intel Blue Box, have a feature in the new CPU that traps on bus condition mask and value registers." I even drew out what I wanted. Well, what do you know, Intel did it. And it remains to this day, and is called "Data breakpoints". Probably the only thing I ever did that will last any length of time, since software has a really short sell-by date as a rule.