There's some penny pinching, for sure - I had a coworker whose brother is on the iPhone hardware team and they have a lot of trouble with samples coming back from manufacturing with the wrong resistor here or a missing capacitor there to save a few bucks, because the factory sees it as overengineering, but doesn't understand the purpose it's built for.
That said, relying on an older processor may actually not save money. Sure, there's a premium on the absolute newest processor, but in general what's cheapest is what is most mass produced Right Now(tm).
I think a z80 on something like this was likely similar to the reasons that NASA control systems typically use the most reliable hardware they can, which means something that has been in use for many years.
For HVAC, maybe a little of each, but also the software may have been written to the z80, and if you change that out, you have to do all the testing you'd have to do if you built a new machine.
I often think back on this old chat I had with my grandfather, where he kind of tilted his head at something I was explaining about 90s tech and said something like:
"Interesting. In my day, we programmed the software to the hardware, it kind of seems like now you all are programming the hardware to the software."
> I had a coworker whose brother is on the iPhone hardware team and they have a lot of trouble with samples coming back from manufacturing with the wrong resistor here or a missing capacitor there to save a few bucks, because the factory sees it as overengineering, but doesn't understand the purpose it's built for.
I find that story utterly implausible.
The day Foxconn makes unapproved changes to Apple designs is the day that...well, never.
That said, relying on an older processor may actually not save money. Sure, there's a premium on the absolute newest processor, but in general what's cheapest is what is most mass produced Right Now(tm).
I think a z80 on something like this was likely similar to the reasons that NASA control systems typically use the most reliable hardware they can, which means something that has been in use for many years.
For HVAC, maybe a little of each, but also the software may have been written to the z80, and if you change that out, you have to do all the testing you'd have to do if you built a new machine.
I often think back on this old chat I had with my grandfather, where he kind of tilted his head at something I was explaining about 90s tech and said something like: