I worked at Tek at the time, although not on the projects using the Tri-Star. The architect was Chuck Sax, who also created the "chuck's Pipe" - a CMOS bucket brigade chip that is the basis of the TDS 3000 series and other DSOs using fast in slow out ADC systems. The Tri-Star was one of the first DSP ASICs optimized for array processing. Its command set is largely modeled after the Motorla MC5600 series, which was handled only single dimensional arrays.
An interesting quirk in scopes using independent DSP for acquisition and display processing is that the main processor can crash and with some scopes, the live waveform continues to be displayed accurately. You can't change any settings or take a screen shot, but it still works as a scope!
Early TDS400 series prototypes showed this effect often.
Steve
