HP-71B SUPERLEX LEX File Manual

[Paul Berger (Canada)]

(12-11-2018 02:17 PM)rprosperi Wrote:  In the HP world, the HP-75C/D and the HP-83/85/86/87 series all used similar processes to extend their BASIC vocabulary. (The same may be true for the 9x00 series desktop computers, I'm not sure how they worked.) The 75 series used RAM (or ROM) based LEX files, similar to the 71B, while the Series-80 used ROM-based extensions (e.g. Graphics ROM added new commands for Graphics features, etc.). The 71 and 75 series LEX files could be copied into the machine's RAM, while for Series-80, the ROM module must be present.

As for the 71B itself, there were many (at least 10?) companies developing/selling LEX files for various kinds of applications, utilities, etc.

I can say for certain that that the 9825 (HPL not BASIC) 9831, 9835 and 9845 all used ROMs to add additional function and I believe this went all the way back to the 9810. When the Rocky Mountain BASIC came along with the 9000 200 and 300 series machines instead of ROM they had optional binaries you could link for some extra function and for device support.