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I would agree with this assessment in most cases. The problem is it's hard to determine which language features perform worse than C. But usually the cost of be

I would agree with this assessment in most cases. The problem is it's hard to determine which language features perform worse than C. But usually the cost of being wrong is low or inconsequential for modern hardware. But it is not true for embedded systems. And the industry disagrees too, and continues to use C because of this.

kllrnohj 7y ago
> But it is not true for embedded systems. And the industry disagrees too, and continues to use C because of this. What resource constrained embedded systems even exist? Fucking lightbulbs run JavaScript these days. SmartCards have been running Java for 20 years. What is the actual market you're so up in arms about that you think is choosing C on technical merits instead of purely inertia? What is this "performance constrained embedded" market to you?
- codesushi42 7y ago
  What is this "performance constrained embedded" market to you? The very definition of embedded systems? I would say it is more much likely the many folks who work on embedded systems in C are right and do so with technical merit. And it is much more likely that it is you who is wrong. Which is quite clear as someone who seems to advocate using JS on embedded hardware for serious tasks. A detail that is seriously amusing in its own right.
  - adrianN 7y ago
    I worked on embedded systems for trains and we used C++. Many people use C just because the chips they target only have a C compiler.
  - pjmlp 7y ago
    Where is that definition written on? Are we talking about PICs with 4KB, or ESP32 that would run circles around the Amstrad PC 1512 that I used to play Defender of the Crown on? A system that already had quite a few high level programming languages available for us to learn programming on. Ah maybe we are speaking about my Visa card running a set of tiny Java Card applications on 256KB, to handle my authentication processes at POS.
  - kllrnohj 7y ago
    > The very definition of embedded systems? Microcontrollers got a lot faster and more powerful over the years. What problem in that space kept up with that speed advancement? Who is paying for hyper-optimized C/asm code instead of just spending an extra $.50 for a dual-core 240mhz ESP32? And who is doing that decision and has decided C is somehow faster than C++? > Which is quite clear as someone who seems to advocate using JS on embedded hardware for serious tasks. I never advocated for it. I said it happened.
- nec4b 7y ago
  Can you do high speed sampling, motor control, signal analysis,... in javascript in realtime? Usually microcontrollers have several memory region with different speeds and access characteristics. Can you fine tune in which parts of the memory part of your javascript program will go into? Can you write a driver for a high speed bus or low speed for that matter in javascript on a mcu?
  - pjmlp 7y ago
    No, but you can use JavaScript on ARM mbed OS, running on $5 ARM-based microcontrollers. https://os.mbed.com/javascript-on-mbed/ https://os.mbed.com/javascript-on-mbed/ On Samsung's SmartThings embedded devices https://smartthings.developer.samsung.com/docs/index.html https://smartthings.developer.samsung.com/docs/index.html SigFox customized IoT solutions https://build.sigfox.com/ https://build.sigfox.com/ Or on the other side from ARM mbed's offering, a beefy ARM 580 MHz with 96 MB (RAM + Flash), using JavaScript alongside Rust. https://tessel.io/ https://tessel.io/ Now if your only definition of embedded are constrained micro-controllers that aren't even able to cope with standard ISO C89 without having additional proprietary compiler extensions, then naturally everything else are just miniature desktop computers. Meanwhile some forward looking companies keep on delivering innovative products.
    - nec4b 7y ago
      Parent poster wondered if there were such embedded applications that can't be done with javascript. And I listed some. That doesn't mean i'm implying that javascript can't be use on a MCU! Where did you get that idea from? I don't think I ever gave a definition of an embedded system, but you can quote me to prove me wrong. A PC embedded in a slot machine for instance can also be called an embedded system. A more important distinction is whether the system must run in real time or not. And you can have a beast of a microprocessor and you will not be able to do low level real time processing with it in javascript.

kllrnohj 7y ago

> But it is not true for embedded systems. And the industry disagrees too, and continues to use C because of this. What resource constrained embedded systems even exist? Fucking lightbulbs run JavaScript these days. SmartCards have been running Java for 20 years. What is the actual market you're so up in arms about that you think is choosing C on technical merits instead of purely inertia? What is this "performance constrained embedded" market to you?

codesushi42 7y ago
What is this "performance constrained embedded" market to you? The very definition of embedded systems? I would say it is more much likely the many folks who work on embedded systems in C are right and do so with technical merit. And it is much more likely that it is you who is wrong. Which is quite clear as someone who seems to advocate using JS on embedded hardware for serious tasks. A detail that is seriously amusing in its own right.
- adrianN 7y ago
  I worked on embedded systems for trains and we used C++. Many people use C just because the chips they target only have a C compiler.
- pjmlp 7y ago
  Where is that definition written on? Are we talking about PICs with 4KB, or ESP32 that would run circles around the Amstrad PC 1512 that I used to play Defender of the Crown on? A system that already had quite a few high level programming languages available for us to learn programming on. Ah maybe we are speaking about my Visa card running a set of tiny Java Card applications on 256KB, to handle my authentication processes at POS.
- kllrnohj 7y ago
  > The very definition of embedded systems? Microcontrollers got a lot faster and more powerful over the years. What problem in that space kept up with that speed advancement? Who is paying for hyper-optimized C/asm code instead of just spending an extra $.50 for a dual-core 240mhz ESP32? And who is doing that decision and has decided C is somehow faster than C++? > Which is quite clear as someone who seems to advocate using JS on embedded hardware for serious tasks. I never advocated for it. I said it happened.
nec4b 7y ago
Can you do high speed sampling, motor control, signal analysis,... in javascript in realtime? Usually microcontrollers have several memory region with different speeds and access characteristics. Can you fine tune in which parts of the memory part of your javascript program will go into? Can you write a driver for a high speed bus or low speed for that matter in javascript on a mcu?
- pjmlp 7y ago
  No, but you can use JavaScript on ARM mbed OS, running on $5 ARM-based microcontrollers. https://os.mbed.com/javascript-on-mbed/ https://os.mbed.com/javascript-on-mbed/ On Samsung's SmartThings embedded devices https://smartthings.developer.samsung.com/docs/index.html https://smartthings.developer.samsung.com/docs/index.html SigFox customized IoT solutions https://build.sigfox.com/ https://build.sigfox.com/ Or on the other side from ARM mbed's offering, a beefy ARM 580 MHz with 96 MB (RAM + Flash), using JavaScript alongside Rust. https://tessel.io/ https://tessel.io/ Now if your only definition of embedded are constrained micro-controllers that aren't even able to cope with standard ISO C89 without having additional proprietary compiler extensions, then naturally everything else are just miniature desktop computers. Meanwhile some forward looking companies keep on delivering innovative products.
  - nec4b 7y ago
    Parent poster wondered if there were such embedded applications that can't be done with javascript. And I listed some. That doesn't mean i'm implying that javascript can't be use on a MCU! Where did you get that idea from? I don't think I ever gave a definition of an embedded system, but you can quote me to prove me wrong. A PC embedded in a slot machine for instance can also be called an embedded system. A more important distinction is whether the system must run in real time or not. And you can have a beast of a microprocessor and you will not be able to do low level real time processing with it in javascript.