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by scruss 1876 days ago
You can still make many HP and compatible laser printers speak HP-GL (well, HP-GL/2) through some arcane PJL commands.

Fun fact: HP-GL is equally compatible with metric and US customary measure as it uses 1/40 mm as its base unit. This just happens to be 1/1016 inches: not a tremendously useful integer factor, but every bit of integer goodness mattered back when peripherals were 8-bit.

2 comments

> Fun fact: HP-GL is equally compatible with metric and US customary measure as it uses 1/40 mm as its base unit. This just happens to be 1/1016 inches

That’s a brilliant hack.

Reminds me of a high precision delta-sigma ADC I saw that had nulls at 60 and 50 HZ.
> This just happens to be

The inch is defined as 2.54 cm, since 1959. You might know this, just thought I'd add this note.

and you guys finally got rid of the US survey foot - the bane of this Canadian's existence when working on big civil jobs in the states. We'll get you guys using proper units afore long