HP-71B Equation Solver

[J-F Garnier]

The documentation of the HP-71 Equation Solver (able to solve an equation for any variable) has been published a few days ago on literature.hpcalc.org.

This solver, written by C. Bunsen, has a special historical interest since it was an early prototype of the 18C/28C SOLVE interface, see the section "History and Inspiration of the Solve Interface" in the HP Journal, Aug. 1987, p. 10.

I knew the existence of this HP-71 solver from the HP Journal but never really tried to locate it until now.
As the documentation provides the names of the BASIC program and support files, it was now easy to find them in Joe Horn's collection.

To try it, just load the EQ, EQLEX and TPKEYS files from the LEXCOL.dat disc image file.
If you already have the ULIB52 LEX installed, then EQLEX is not needed (actually, it's better to use ULIB52 that fixes some bugs).
You also need the MATH ROM.

Thanks to Eric for scanning and sharing this up-to-now unreleased document, and thanks to the donor !

J-F

(edited: corrected the link - thanks Mark)