9 ms·

I remember a conversation I had with a friend's father, an HVAC engineer. He brought home a control board one-time, showed me the sensor inputs and control outp

by bane 11y ago

I remember a conversation I had with a friend's father, an HVAC engineer. He brought home a control board one-time, showed me the sensor inputs and control outputs. I don't remember how many there were, but let's say a dozen of each. He described how a sensor in would connect to this spot and feed the system temperatures from a sensor in some remote part of the building. The control output would then go to the appropriate HVAC system and turn on/off A/C, heat or whatever to get the temperature to what it needed to be at. The system would spider out around the building with these sensors and regulate the building's temperature. At the heart of the board (which looked like a PC motherboard) was the CPU, a z80, already hilariously ancient when he showed this to me. So I asked him "why not use a more modern CPU?" He responded, "why? This z80 can control an office building's entire HVAC system, and poll each sensor 200 times a second, how many times per second do you need? Temperature in a zone doesn't change that fast." It was my introduction to the concept of "Lateral Thinking with Withered Technology" https://en.wikipedia.org/wiki/Gunpei_Yokoi#Lateral_Thinking_with_Withered_Technology https://en.wikipedia.org/wiki/Gunpei_Yokoi#Lateral_Thinking_...

userbinator 11y ago
Z80s are still available new and in IP core form for integration into SoCs... as is the 6502, 8051, and several other "classic" MCUs designed in the late 70s/early 80s. As I'm typing this my keyboard's controller is an 8051 variant, the touchscreen of my phone also uses an 8051, the mouse has a 6502, and the monitors in front of me have an 80186 core in them. They are fast enough for the task, cheap, and development tools widely available, so they really don't need to be replaced.
- qanael 11y ago
  It's kind of mind blowing that our cheap peripherals are driven by what used to be top-of-the-line processors only a few decades ago. I guess all that firmware has to run on something.
  - vidarh 11y ago
    As I mentioned in another comment, already the ca. 1987 Amiga 2000 in this article had a 6502 compatible core on the keyboard controller, and some same era hd controllers had Z80's on them - they were cheap already then.
- vidarh 11y ago
  Interesting considering the article, it was a defining part of Commodore hardware design that they compensated for slow CPU's by using co-processors all over the place, including putting a 6502 compatible CPU in the keyboard controller for the A500 and A2000... (But you'd also find this spilling over into 3rd party hardware: My HD controller for my Amiga 2000 back in the day had a Z80 on it. That machine was totally schizophrenic: In addition to the 6502 core on the keyboard, the M68k main CPU and the Z80 on the HD controller it also had an x86 on a bridge board - the A2000 had both Amiga-style Zorro slots and ISA slots, including one slot where both connectors were in line where you could slot in a "bridge board" with an 8086 that effectively gave you a PC inside your Amiga, with the display available in a window on the Amiga desktop).
- aswanson 11y ago
  Do you think its better to teach uni students on new processors and tools e.g. Freescale, ARM, etc. or on older z-80, 80186 cpus?
  - pkaye 11y ago
    Working on the older CPUs is more approachable to understanding all the low level details plus it makes you appreciate all that the newer CPUs offer. However when actually working, I don't think one should work with an older CPU unless it really makes sense (sufficient computer power, low power requirements, etc.) Working with a powerful CPU lets you focus on the job at hand instead of the idiosyncrasies.
    - revelation 11y ago
      I don't think this is true at all, older CPUs are not a "more purified" and "cleaner" version of todays, they have the same and often considerably more cruft and crazyness. To work with them is to teach bad habits and useless skills.
      - JoeAltmaier 11y ago
        Just look at the 6502. No two instructions follow the same pattern - every one is a moss-covered three-handled family credenza, to quote the good Doctor.
        pkaye 11y ago
        The x86 family is the same.
        JoeAltmaier 11y ago
        Oh there is quite a lot of consistency in the structure of instructions across the basic set - register numbering, many instructions allow full register and addressing modes. The 6502 had pretty much no two instructions the same.
- ChickeNES 11y ago
  What mouse uses a 6502?
  - userbinator 11y ago
    This one: http://www.mcuic.com/bookpic/200811516244620817.pdf http://www.mcuic.com/bookpic/200811516244620817.pdf (Look at page 9. This IC is found in a lot of generic mouses.)
- selimthegrim 11y ago
  TI runs all its low-level calculator stuff on Z80 emulators which are then helpfully run by whatever actual chip they are putting in the calculators these days.
  - JonathonW 11y ago
    Nope; with one exception, the Z80-family calculators are still run by real, bona-fide Z80s (or, in the case of the new TI-84 Plus CE, an eZ80). (That "one exception" was the TI-84 Keyboard for the original Nspire, which did run the 84's firmware in a Z80 emulator on the Nspire's ARM processor.)
macNchz 11y ago
>It was my introduction to the concept of "Lateral Thinking with Withered Technology" https://en.wikipedia.org/wiki/Gunpei_Yokoi#Lateral_Thinking_.. https://en.wikipedia.org/wiki/Gunpei_Yokoi#Lateral_Thinking_.... Thanks for sharing this, I love finding creative new ways to take advantage of 'tried & true' technology and it's something that regularly feeds into how I build software–sometimes to the displeasure of colleagues who are most interested in the shiniest new tools. It's interesting to read about how this sort of thinking worked for Nintendo.
- seanp2k2 11y ago
  Why write your own 10-line function to do it when you could use this library and do it with 3 (not including the 3k line lib)
ChuckMcM 11y ago
This is so true, and even today with new designs you end up with overkill. A Cortex M0 (32 bit ARM system) with 128K of flash and 64K of RAM is 75 cents in quantity. That means the processor complex is essentially "free" with respect to the cost of the other bits (sensors, actuators, communication over distance). The risk is that with all that "extra power" the programmer decides to use it creatively for something like "A built in web server to show you status of everything" and that "feature" requires you connect it to the wider network, and that "webserver" never gets patched, and now you have an HVAC system which becomes the exploit vector to get into a much bigger facility/network. All because designing in a "limited" computer didn't make economic sense, and programmers couldn't help but use the extra CPU capacity that was available. That is what makes IoT a challenge / bad-idea to a lot of people.
- deleted 11y ago
  [deleted]
- bliti 11y ago
  Spot on. Programmers in general are not well-versed in security. I don't mean you, the reader of this comment. But as a collective. The other people who write code through which you can pass buses full of black hats. Not you. Web applications with huge budgets get owned by common mistakes. And those web applications don't have access to anything but data. Imagine having all those same, eh, security issues, in devices that can interact with the real world. I really don't want my microwave to suddenly turn on and keep going for hours at time while I'm out of the house. This comment is purely fictional. IoT is perfect.
  - gpvos 11y ago
    Fnord.
- deleted 11y ago
  [deleted]
  - toomuchtodo 11y ago
    Constrained resources encourages simplicity by design. Use only whats necessary, no more, no less.
serve_yay 11y ago
At some point it may become cost-prohibitive (or unwieldy in some other way) to continue to manufacture such chip designs, even though many applications may not require additional raw horsepower.
superuser2 11y ago
Why? So you can use modern, friendly UIs to control it instead of scary there-be-dragons only-one-guy-in-facilities-is-allowed-to-touch-it Win32 apps.
lurkinggrue 11y ago
At best can replace it with a Raspberry PI instead of a full on PC.
deleted 11y ago
[deleted]
deleted 11y ago
[deleted]
LordKano 11y ago
From time to time, I am greeted with looks of shocked disbelief when a younger employee finds out how much of my employer's business gets done on OpenVMS Alphas and IBM Mainframes. They think it's stupid that we're not running it all on HP servers in the data center. The thought never occurs to them that it's rock solid, only needs quarterly patching(at most) and has had 20+ years of tweaks that make it fit our needs. We don't need to replace it, yet.
- nickpsecurity 11y ago
  Not to mention there's VMS clusters with 20+ years of uptime. The systems, especially Alphas, were so reliable that at least one sysadmin forgot how to restart them and had to consult the manual lol. I wish they made a good desktop. I'd have used it and probably lost less work. ;) A link for you: http://h71000.www7.hp.com/openvms/brochures/commerzbank/commerzbank.pdf http://h71000.www7.hp.com/openvms/brochures/commerzbank/comm... Notice how "all systems crashed" from heat except the AlphaServer. That's great engineering, right there. It's why I wish they were still around outside eBay. That plus PALmode: most benefits of microprogramming without knowing microprogramming. :)
- danjayh 11y ago
  When people really need something that's reliable, there's really no limit to how much effort can be put into producing a system with unfailing integrity and availability. Take, for example, the lockstep facility on certain IBM processors: https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/292763D22B80DFEF872570C1006DF928/$file/750GX_Lockstep_3-19-08.pdf https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/29... You can take two or more of them, run identical software on them, and compare their output on a cycle-by-cycle basis. Now, the 750GX series may be a bit out of date in the modern era ... but good luck achieving that level of paranoid system integrity with just about any truly modern system. One thing that I think they don't teach so well in most colleges is that a system's compute performance is not always the most important measurement of the system's capability.
rtpg 11y ago
the counter to lateral thinking nowadays is power efficiency. Imagine underclocking the iphone 6 processor to 1st gen iphone screens. I image you'd get quite a bang for your buck on that one. Though I am a big proponent of lateral thinking in general, for battery powered devices the optics change a little I think.

by bane 11y ago

userbinator 11y ago

Z80s are still available new and in IP core form for integration into SoCs... as is the 6502, 8051, and several other "classic" MCUs designed in the late 70s/early 80s. As I'm typing this my keyboard's controller is an 8051 variant, the touchscreen of my phone also uses an 8051, the mouse has a 6502, and the monitors in front of me have an 80186 core in them. They are fast enough for the task, cheap, and development tools widely available, so they really don't need to be replaced.

qanael 11y ago
It's kind of mind blowing that our cheap peripherals are driven by what used to be top-of-the-line processors only a few decades ago. I guess all that firmware has to run on something.
- vidarh 11y ago
  As I mentioned in another comment, already the ca. 1987 Amiga 2000 in this article had a 6502 compatible core on the keyboard controller, and some same era hd controllers had Z80's on them - they were cheap already then.
vidarh 11y ago
Interesting considering the article, it was a defining part of Commodore hardware design that they compensated for slow CPU's by using co-processors all over the place, including putting a 6502 compatible CPU in the keyboard controller for the A500 and A2000... (But you'd also find this spilling over into 3rd party hardware: My HD controller for my Amiga 2000 back in the day had a Z80 on it. That machine was totally schizophrenic: In addition to the 6502 core on the keyboard, the M68k main CPU and the Z80 on the HD controller it also had an x86 on a bridge board - the A2000 had both Amiga-style Zorro slots and ISA slots, including one slot where both connectors were in line where you could slot in a "bridge board" with an 8086 that effectively gave you a PC inside your Amiga, with the display available in a window on the Amiga desktop).
aswanson 11y ago
Do you think its better to teach uni students on new processors and tools e.g. Freescale, ARM, etc. or on older z-80, 80186 cpus?
- pkaye 11y ago
  Working on the older CPUs is more approachable to understanding all the low level details plus it makes you appreciate all that the newer CPUs offer. However when actually working, I don't think one should work with an older CPU unless it really makes sense (sufficient computer power, low power requirements, etc.) Working with a powerful CPU lets you focus on the job at hand instead of the idiosyncrasies.
  - revelation 11y ago
    I don't think this is true at all, older CPUs are not a "more purified" and "cleaner" version of todays, they have the same and often considerably more cruft and crazyness. To work with them is to teach bad habits and useless skills.
    - JoeAltmaier 11y ago
      Just look at the 6502. No two instructions follow the same pattern - every one is a moss-covered three-handled family credenza, to quote the good Doctor.
      - pkaye 11y ago
        The x86 family is the same.
        JoeAltmaier 11y ago
        Oh there is quite a lot of consistency in the structure of instructions across the basic set - register numbering, many instructions allow full register and addressing modes. The 6502 had pretty much no two instructions the same.
ChickeNES 11y ago
What mouse uses a 6502?
- userbinator 11y ago
  This one: http://www.mcuic.com/bookpic/200811516244620817.pdf http://www.mcuic.com/bookpic/200811516244620817.pdf (Look at page 9. This IC is found in a lot of generic mouses.)
selimthegrim 11y ago
TI runs all its low-level calculator stuff on Z80 emulators which are then helpfully run by whatever actual chip they are putting in the calculators these days.
- JonathonW 11y ago
  Nope; with one exception, the Z80-family calculators are still run by real, bona-fide Z80s (or, in the case of the new TI-84 Plus CE, an eZ80). (That "one exception" was the TI-84 Keyboard for the original Nspire, which did run the 84's firmware in a Z80 emulator on the Nspire's ARM processor.)

macNchz 11y ago

>It was my introduction to the concept of "Lateral Thinking with Withered Technology" https://en.wikipedia.org/wiki/Gunpei_Yokoi#Lateral_Thinking_.. https://en.wikipedia.org/wiki/Gunpei_Yokoi#Lateral_Thinking_.... Thanks for sharing this, I love finding creative new ways to take advantage of 'tried & true' technology and it's something that regularly feeds into how I build software–sometimes to the displeasure of colleagues who are most interested in the shiniest new tools. It's interesting to read about how this sort of thinking worked for Nintendo.

seanp2k2 11y ago
Why write your own 10-line function to do it when you could use this library and do it with 3 (not including the 3k line lib)

ChuckMcM 11y ago

This is so true, and even today with new designs you end up with overkill. A Cortex M0 (32 bit ARM system) with 128K of flash and 64K of RAM is 75 cents in quantity. That means the processor complex is essentially "free" with respect to the cost of the other bits (sensors, actuators, communication over distance). The risk is that with all that "extra power" the programmer decides to use it creatively for something like "A built in web server to show you status of everything" and that "feature" requires you connect it to the wider network, and that "webserver" never gets patched, and now you have an HVAC system which becomes the exploit vector to get into a much bigger facility/network. All because designing in a "limited" computer didn't make economic sense, and programmers couldn't help but use the extra CPU capacity that was available. That is what makes IoT a challenge / bad-idea to a lot of people.

deleted 11y ago
[deleted]
bliti 11y ago
Spot on. Programmers in general are not well-versed in security. I don't mean you, the reader of this comment. But as a collective. The other people who write code through which you can pass buses full of black hats. Not you. Web applications with huge budgets get owned by common mistakes. And those web applications don't have access to anything but data. Imagine having all those same, eh, security issues, in devices that can interact with the real world. I really don't want my microwave to suddenly turn on and keep going for hours at time while I'm out of the house. This comment is purely fictional. IoT is perfect.
- gpvos 11y ago
  Fnord.
deleted 11y ago
[deleted]
- toomuchtodo 11y ago
  Constrained resources encourages simplicity by design. Use only whats necessary, no more, no less.

serve_yay 11y ago

At some point it may become cost-prohibitive (or unwieldy in some other way) to continue to manufacture such chip designs, even though many applications may not require additional raw horsepower.

superuser2 11y ago

Why? So you can use modern, friendly UIs to control it instead of scary there-be-dragons only-one-guy-in-facilities-is-allowed-to-touch-it Win32 apps.

lurkinggrue 11y ago

At best can replace it with a Raspberry PI instead of a full on PC.

deleted 11y ago

[deleted]

deleted 11y ago

[deleted]

LordKano 11y ago

From time to time, I am greeted with looks of shocked disbelief when a younger employee finds out how much of my employer's business gets done on OpenVMS Alphas and IBM Mainframes. They think it's stupid that we're not running it all on HP servers in the data center. The thought never occurs to them that it's rock solid, only needs quarterly patching(at most) and has had 20+ years of tweaks that make it fit our needs. We don't need to replace it, yet.

nickpsecurity 11y ago
Not to mention there's VMS clusters with 20+ years of uptime. The systems, especially Alphas, were so reliable that at least one sysadmin forgot how to restart them and had to consult the manual lol. I wish they made a good desktop. I'd have used it and probably lost less work. ;) A link for you: http://h71000.www7.hp.com/openvms/brochures/commerzbank/commerzbank.pdf http://h71000.www7.hp.com/openvms/brochures/commerzbank/comm... Notice how "all systems crashed" from heat except the AlphaServer. That's great engineering, right there. It's why I wish they were still around outside eBay. That plus PALmode: most benefits of microprogramming without knowing microprogramming. :)
danjayh 11y ago
When people really need something that's reliable, there's really no limit to how much effort can be put into producing a system with unfailing integrity and availability. Take, for example, the lockstep facility on certain IBM processors: https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/292763D22B80DFEF872570C1006DF928/$file/750GX_Lockstep_3-19-08.pdf https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/29... You can take two or more of them, run identical software on them, and compare their output on a cycle-by-cycle basis. Now, the 750GX series may be a bit out of date in the modern era ... but good luck achieving that level of paranoid system integrity with just about any truly modern system. One thing that I think they don't teach so well in most colleges is that a system's compute performance is not always the most important measurement of the system's capability.

rtpg 11y ago

the counter to lateral thinking nowadays is power efficiency. Imagine underclocking the iphone 6 processor to 1st gen iphone screens. I image you'd get quite a bang for your buck on that one. Though I am a big proponent of lateral thinking in general, for battery powered devices the optics change a little I think.