4 ms·

I've always wondered if a Soviet block made a clone that was better in some way, or if they ever came up with their own CPU architecture. Didn't IBM have an AL

I've always wondered if a Soviet block made a clone that was better in some way, or if they ever came up with their own CPU architecture. Didn't IBM have an ALU design that were more harden again calculation errors?

metaphor 6y ago
> Didn't IBM have an ALU design that were more harden again calculation errors? I'm genuinely confused what is meant by this in practice. Like some sort of redundant ALU architecture or rad hard encapsulation?
- krallja 6y ago
  ‘kens has an article about IBM qui-binary arithmetic: http://www.righto.com/2015/10/qui-binary-arithmetic-how-1960s-ibm.html http://www.righto.com/2015/10/qui-binary-arithmetic-how-1960... this might be what is referenced?
  - xellisx 6y ago
    That's what I was thinking about!
- dbcurtis 6y ago
  It could mean either. Rad-hard parts are used in satellites. I am not familiar with the current crop of rad-hard parts. I did work as a CPU logic desiger at Amdahl. We had full parity through-checking, so an ALU intermittent logic error would raise a parity exception. Certainly IBM would have had the same, it was standard SOTA reliability logic for the era of mainframes when I was a designer.
Miiko 6y ago
> if [Soviet block] ever came up with their own CPU architecture. To the best of my knowledge, BESM-6 and Elbrus were not clones https://en.wikipedia.org/wiki/Elbrus_(computer) https://en.wikipedia.org/wiki/Elbrus_(computer)
flyinghamster 6y ago
One that shows up on HN occasionally is Setun: https://en.wikipedia.org/wiki/Setun https://en.wikipedia.org/wiki/Setun Setun used balanced ternary logic instead of binary logic. Each trit could be -1, 0, or +1. For numeric values, there was no need to store a sign, since the sign of a number would be inherent in its ternary value. Then the Soviets decided that it would be easier and faster to just copy western computers, and the concept wasn't developed any further.
- xellisx 6y ago
  I know there has been recent activity in developing a ternary CPU. https://hackaday.com/2016/12/16/building-the-first-ternary-microprocessor/ https://hackaday.com/2016/12/16/building-the-first-ternary-m...
SomeoneFromCA 6y ago
USSR made an incompatible "clone" of Apple-II, called AGAT with better graphics. Also 8086 clone VM86 AFAIK was significantly reingennered. Some PDP-11 clones were also designed from the scratch.

metaphor 6y ago

> Didn't IBM have an ALU design that were more harden again calculation errors? I'm genuinely confused what is meant by this in practice. Like some sort of redundant ALU architecture or rad hard encapsulation?

krallja 6y ago
‘kens has an article about IBM qui-binary arithmetic: http://www.righto.com/2015/10/qui-binary-arithmetic-how-1960s-ibm.html http://www.righto.com/2015/10/qui-binary-arithmetic-how-1960... this might be what is referenced?
- xellisx 6y ago
  That's what I was thinking about!
dbcurtis 6y ago
It could mean either. Rad-hard parts are used in satellites. I am not familiar with the current crop of rad-hard parts. I did work as a CPU logic desiger at Amdahl. We had full parity through-checking, so an ALU intermittent logic error would raise a parity exception. Certainly IBM would have had the same, it was standard SOTA reliability logic for the era of mainframes when I was a designer.

Miiko 6y ago

> if [Soviet block] ever came up with their own CPU architecture. To the best of my knowledge, BESM-6 and Elbrus were not clones https://en.wikipedia.org/wiki/Elbrus_(computer) https://en.wikipedia.org/wiki/Elbrus_(computer)

flyinghamster 6y ago

One that shows up on HN occasionally is Setun: https://en.wikipedia.org/wiki/Setun https://en.wikipedia.org/wiki/Setun Setun used balanced ternary logic instead of binary logic. Each trit could be -1, 0, or +1. For numeric values, there was no need to store a sign, since the sign of a number would be inherent in its ternary value. Then the Soviets decided that it would be easier and faster to just copy western computers, and the concept wasn't developed any further.

xellisx 6y ago
I know there has been recent activity in developing a ternary CPU. https://hackaday.com/2016/12/16/building-the-first-ternary-microprocessor/ https://hackaday.com/2016/12/16/building-the-first-ternary-m...

SomeoneFromCA 6y ago

USSR made an incompatible "clone" of Apple-II, called AGAT with better graphics. Also 8086 clone VM86 AFAIK was significantly reingennered. Some PDP-11 clones were also designed from the scratch.