[sdiy] 4-bit encoder?

[Rainer Buchty]

On Tue, 13 Oct 2020, Roman Sowa wrote:

> 2. If something with any kind of firmware in it will break in 40 
> years, there will be some clever geek around (not born today yet) who 
> will not worry about vintage chips but make functional replacement 
> using 40-years-into-the-future technology.

Stuff like this could be eased if either the source code is released 
upon ceasing to market a device or at least suitable datasheets are 
provided.

Early 80s stuff is still easy enough to rev-eng, but the younger it 
gets, the more effort it needs.

Modern SoC-based machines are IMO ultimately doomed w/o released
documentation because even if people manage to rev-eng the (often
encrypted) OS update binaries, they would still need to come up with a
complete SoC solution, including the used CPU and whatever peripherals
and hardware accelerators employed. Going *this* road takes a lot of 
enthusiasm -- and time.

> 3. If David has a choice to do it with 40 chips and it makes him 
> happy, then I can fully understand it, maybe even admire it.

There's always one who likes to make it more interesting:

 	http://www.jogis-roehrenbude.de/Leserbriefe/Bruegmann-Digital-Roehren-Clock/Digital-Roehrenuhr.htm

(The pictures speak for themselves.)

> My plan for retirement is to make a polsynth with patch memory and all 
> bells and whistles not using a single line of code. No micros, no 
> FPGAs, just plain logic and analog chips. Now try to change my mind.

So you're talking about elaborate state machines spitting out a variety
of control signals -- which essentially is microcoding and hence
software :)

Best,
         Rainer