Hewlett-Packard was an electronic engineering, semiconductor, and computing company from the beginning (the first product they sold was an audio distortion analyzer, it used a creative circuit to achieve high performance at minimum cost), they used to do serious and innovative R&D. There were the glorious days when Hewlett-Packard makes state-of-art test equipment and semiconductor devices, developed in-house enterprise computer systems like HP-UX system and PA-RISC CPUs, first-generation of scientific and programmable handheld calculators, etc., not just today's customer printers and laptops.

e.g. I recently found a datasheet of an IC in an amateur radio gear, it were really the glorious days. Those chips with an HP logo (or a Motorola logo) are really cool.

> The INA series of MMICs is fabricated using HP’s 25 GHz f_max, ISOSAT™-I silicon bipolar process which uses nitride self-alignment, submicrometer lithography, trench isolation, ion implantation, gold metallization and polyimide intermetal dielectric and scratch protection to achieve excellent performance, uniformity and reliability.

Around 2000s, the EE & semiconductor department became an independent company, Agillent, and later Keysight.

I think the last major innovation at HP was probably memristor that was supposed to be the next evolution of digital logic and storage, and HP claimed that it was developing a memristor computer system. Unfortunately, it failed to materialize.