Hex numpads?

[StevieC]

Skimming through a table of USB keyboard usage codes, I see codes for numpad A through F, keys for "binary", "octal", "decimal", and "hex" which implies the existence of keyboards with such keys on their numpads. Do such keyboards physically exist, and if so, what layouts do they use for their numpads?

[kps]

It looks like that group of codes were oriented to a hex-calculator style keypad. Unfortunately USB hasn't published any rationale for their choices. If they were used, it wasn't on anything in the ‘mainstream’ PC lineage — Windows and Linux both ignore them.

[depletedvespene]

Weeeeeelllll...

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[Inxie]

s-l1600.jpg

That's not even remotely comparable or the same. Yes it's the same keys, but that's where similarities end.

[kps]

Many hardware tools (e.g. logic analyzers) and single-board computers had hex keypads, but that's not really the same as a hex keypad on a regular text keyboard (or using the same interface as a regular text keyboard).

[depletedvespene]

Well, as long as we don't know the underlying rationale for the USB protocol choices, we can only guess... and I would hazaphard that consideration for these kinds of keypads was given.

[depletedvespene]

Heck, looking at the keycode table, it ALSO has (beyond "Keypad A" .. "Keypad F") codes for Backspace, Tab, XOR, a boatload of symbols used as math operators, and even "Memory Store", "Memory Add" and base selectors (Binary, Octal, Decimal and Hexadecimal). The more I look at it, the more it looks like this was all added to satisfy the needs of advanced scientific calculators.

[kps]

Found one: the Tektronix PRISM logic analyzers. It's even the right age that the people doing the USB hardware layer might have had one.

[Weezer]

I don't own any numberpads, but my guess would be that the extra available scancodes were created to allow for potential flexibility in hypothictical application scenarios, not necessarily because there was something that readily demanded their existence. It's also possible that the extra codes were meant to be mapped to a macro pad or something. The USB standard was created by multiple big name companies so it's also possible that one of them had some very specific equipment that they demanded be accomodated so I cannot say. I know windows has a feature in the registry that can be enabled for expanded alt + numpad entry with hexadecimal characters. This can be used to create more advanced unicode characters on the fly, so at least in theory a hex numpad would seem to slot in nicely with Windows for that specific use case.