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  • Eric Brombaughemeb
    Sep 14, 2026, 9:08 PM

    Long ago I had a summer job at the University of Oregon Physics Dept, working for Prof. Russell Donnelly and it was like drinking from a firehose of science and computing. In some spare moments I played with an HP85 Personal Computer, working through some of the examples in the owners manual. One of these examples was a lightbulb moment that showed me how trigonometry could be useful - a simple circle drawing program in HP BASIC:

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    An example program in HP BASIC from the HP85 Users Manual for drawing an ellipse. 10 GCLEAR 20 DEG 30 SCALE -2,2,-4,4 32 | DRQ A CIRCLE 40 MOVE 1,0 50 FOR A=0 TO 360 STEP 15 60 DRAW COS(A),SIN(A) 70 NEXT A 80 END
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  • Eric Brombaughemeb
    Sep 14, 2026, 9:17 PM

    Last year I inherited an HP85 from a friend and it's been sitting in my office ever since. Today I powered it up and keyed in that program. With a few slight changes, here's what it looks like.

    Yes, it's slow and low-res, but in 1980 256x192 monochrome graphics with floating point was amazing stuff. If only computers these days could be so transparent and friendly.

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    Image attached toot
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