HP 7470A plotter -- repairing/replacing paper feed rollers

On 4 Sep 2011 at 17:44, Tony Duell wrote: It could have been the 7470A--it was too long ago to recall which it was. I just borrowed the plotter and recall the mylar foil-packaged pens--and I had a good-sized box of them (apparently the store tossed all the pens they had in with the plotter). That may be what triggered the 7440 memory. IIRC, the documentation definitely called a Centronics interface model out. For all I know, I hooked BIOS interrupt 14H. Heck, it was less than a week's adventure more than 20 years ago. No point to having it now--I have a GPIB interface card. Just another misadventure in a long line of misadventures. A couple of years laterr, I got a call from Greg Mansfield, who was working for Cray at the time. He prompted me to reprise my code and turn it into a library of subroutines, which I did--and added considerable functionality. I don't know if that was ever published, though I gave my blessing to do so. It could be that Greg had the 7440A. Neural rot, dammit. Just like the IBM product manager in last month's IEEE Computer who refers to the "Zilog 6502". --Chuck