What is the history of the keys &6 (8 )9 keyboard layout?

[McArti0]

Atari 400, 800xl had always (9  )0 keys.
C64 had (8. )9 keys like Amstrad and BBC,Dragon, Acorn but not Archimedes from 1987.

IBM portable had mix layout.
https://en.m.wikipedia.org/wiki/File:IBM_5155_(1).jpg

PCW8256 had (9  )0 but "2 yet.

Is the Amstrad layout extinct? It doesn't exist today.

[eto]

My guess would be that they took what the liked/knew (BBC Micro) and adjusted it slightly, so it can fit their cost-optimised keyboard matrix solution.

[Bryce]

Was there ever really a standard? Even today French Azerty, German Qwertz and US and UK Qwerty all have different layouts.

Bryce.

[McArti0]

Strangely enough, I couldn't find any old British typewriters with (8   )9.

[ZorrO]

MSX and Apple2 sometimes using one and sometimes another system. Atari ST, Amiga and PCW german version have () on 89 keys, but english on 90.
Place for CapsLock, Ctrl, Alt keys jumps in different computers either. Only Atari ST and use early IBM PC places, what happend?
Delete sometimes is on left from Backspace and sometimes on right, why?

C= C16, C116 and C+4 compatible machines, but each of them chars £*= have in different places. For what?

I don't understand why Amarican and British keyboards swaps " and #. In 8bit times everybody had British system with " on 2, even USA. So WTF?

[Egg Master]

Japanese keyboards!

May be we got a close layout into the 80s, because...

[Bread80]

I've spent a lot of time reverse engineering the schematics of the Datapoint 2200. It's a machine from circa 1970 with a very slow TTL processor, very little memory and no ROM (it bootstraps off tapes). (It's also the machine which became the Intel 8008 processor and over many generations begat the current day Pentiums).

It has a keyboard which returns ASCII codes, and it's all done in hardware. Why? Because converting scan codes to ASCII requires memory (which it doesn't have) and processor cycles (which it also doesn't have). I suspect a lot of early machines did the same.

With that in mind, take a look at an ASCII table. Everyone knows that the codes for upper case letters are one bit different to those for lower case. Very few people realise that, on these old keyboard layouts, the same applies to pretty much every other key too. So, the symbols on number keys are one bit different to the numbers, and the symbol only keys bear symbols one bit different to each other.

Therefore the pairings of symbols was originally done to make the hardware easier. (Or, more likely, the ASCII codes where intentionally chosen to reflect pre-existing keyboard layouts).

[Bryce]

I've spent a lot of time reverse engineering the schematics of the Datapoint 2200. It's a machine from circa 1970 with a very slow TTL processor, very little memory and no ROM (it bootstraps off tapes). (It's also the machine which became the Intel 8008 processor and over many generations begat the current day Pentiums).

It has a keyboard which returns ASCII codes, and it's all done in hardware. Why? Because converting scan codes to ASCII requires memory (which it doesn't have) and processor cycles (which it also doesn't have). I suspect a lot of early machines did the same.

With that in mind, take a look at an ASCII table. Everyone knows that the codes for upper case letters are one bit different to those for lower case. Very few people realise that, on these old keyboard layouts, the same applies to pretty much every other key too. So, the symbols on number keys are one bit different to the numbers, and the symbol only keys bear symbols one bit different to each other.

Therefore the pairings of symbols was originally done to make the hardware easier. (Or, more likely, the ASCII codes where intentionally chosen to reflect pre-existing keyboard layouts).

That's extremely interesting. I never even considered that someone might plan the hardware in such a way as to make use of the hardware bit pattern in order to simplify the software ASCII decoding. What a cool idea! If that's what they actually did.

Bryce.