HP Portable Plus ... until 2039?

[Jim Horn]

The 110 Portable and Portable Plus still have a warm spot in my heart - I used my Portable for years as a preferred note taker and word processor. While limited compared to later machines, its ~20 hour battery run time and superb keyboard made it really handy for that.

When Sam Chau first engineered how to modify the Portable's motherboard to give it 512k of RAM instead of the standard 272k, we figured we should be able to modify PAM's routines that set the partition between user RAM and Drive A:. But we were surprised to learn that HP had lost the source code, making doing so difficult at best. Sam ended up writing his own disk driver routine to use the extra 240k as drive B:.

We joked that the Portable was "PC Compatible" in that it was theoretically possible to write a program that ran on it and on an IBM PC but that it had never been done. That was a sarcastic stretch as many DOS utilities ran fine. The trick was to use the proper BIOS calls rather than any attempt to access hardware directly.

The macro assembler HP sold as an option worked well too, judging from Sam's work with it.

Do enjoy your Portable family machines! Mine has since been given to one of the very active Forum members along with the many binders of documentation. May they all continue to serve you well!