plotters again

Inspired by all that talk of plotters last week, I lugged the box containing the HP9872A upstairs and opened it for the first time in 6 years. A few repairs later, an evening in a comfy chair with the manuals (it's nice to have manuals for a change), and some doodling on the 9815 calculator which drives it, and the plotter is zip'in and zoom'in about. Yup, it's pretty neat, esp. with the built-in character generation with scaling. The weak point in this scenario however, is the torture of programming the 9815 and problems with the tape cartridges and drive of the 9815. Those cartridges and drive may have been OK in the day, but today with the gooey wheel issue and failing elastic bands in the cartridges they're nothing one wants to rely on. Given that the plotter uses HP-GL as the control language, I began to think along the same lines as Chuck wrote about a day ago: building a simple parallel interface to the plotter HP-IB port that does just the data transfer (minus all the HP-IB device selection, etc. functions) to connect it up to a more flexible/modern source/controller machine. That's just a thought at the moment so there's no immediate need, but I'm wondering if there are any HP-GL plot files (or collection thereof) out there which would then be available to simply throw down the line at the plotter to draw cute stuff and exercise the plotter. I'm not really thinking of programs or graphics software packages that generate HP-GL, as that would require particular hardware/systems to execute on. Rather: just straight ASCII-text HP-GL files that were previously generated or hand-coded, sort of in the same spirit as 'ASCII-art' was produced.