HP 7090A - Some more detailed plots

Having the pen selection & Geneva wheel issues addressed, I wanted to try some more detailed plots. This video is in real time so the first plot ends at 3:50 and the second at 7:12. Code is available at https://github.com/TGoodhew/HPGLTest.

Chapters
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0:00 First plot
3:50 Flipping the paper
4:14 Second plot
7:12 Plots complete