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They build an open source CPU to run an open source OS namely Linux to make IoT applications possible. Okay, But then they mention in the beginning with Linux

by PinguTS 10y ago

They build an open source CPU to run an open source OS namely Linux to make IoT applications possible. Okay, But then they mention in the beginning with Linux you need minimum 8 MiB Ram, because "less is awkward". To be honest 8 MiB is a lot for embedded, for IoT. Normally we deal with way less then 1 MiB. Especially in IoT I need low power and less components. A state of the art Cortex M0 has somewhere of 256 KiB of Ram. With that they basically prove, that Linux is not suited for IoT. Is that the point they want to make? Really?

stephen_g 10y ago
It's only a matter of time before that kind of RAM size is normal for very low-power and low-cost devices though, and if running Linux makes your development faster or easier or whatever then it's good to have it as an option. It really depends on the application, how much processing power you need, etc. but more options are only a good thing. Remember that the 'T' in IoT doesn't just mean little things - these guys are talking about devices that monitor large transformers and power distribution equipment (critical electrical infrastructure). It's likely that an IoT device for that would be doing a lot more than, say, a smart meter for a home for which Linux probably would be overkill.
- nomoch 10y ago
  The problem I have with that is that I hear it every decade about niche-x. And people are right, but as soon as costs drop enough that niche-x can support the full desktop stack there's now a niche-y where you're still stuck with hundreds of bytes of memory, the market is x10 as big, and you're using the same tools you were using a decade ago. An 8-bit micro controller will be with us forever because it is the smallest computer that is useful for more than trivial tasks, it will just keep getting smaller and smaller. I won't be surprised if the first space ship to land on a different solar system has trillions of 8-bit computers on it the size of atoms.
- gchadwick 10y ago
  > It's only a matter of time before that kind of RAM size is normal for very low-power and low-cost devices though Really? SRAM isn't cheap and takes power, DRAM cheaper (especially once process/packaging technology means you can place it on the same die or in the same package as the processor) but still costs power. Fundamentally if you want very low-power you're gonna go for lowest RAM possible. Ditching it is an easy way to save power. Even if RAM is cheap using 1/32th of it (8mb vs 256k) makes things cheaper still. Important if you're going for very low-cost.
  - rjsw 10y ago
    Once you go outside the size of RAM chips that are used in mass-market devices the cost goes up by a lot.
Avshalom 10y ago
They built it for high assurance applications where being able to review absolutely everything from ground is important foremost. IoT is just an application the cpu is also well suited for.

by PinguTS 10y ago

stephen_g 10y ago

It's only a matter of time before that kind of RAM size is normal for very low-power and low-cost devices though, and if running Linux makes your development faster or easier or whatever then it's good to have it as an option. It really depends on the application, how much processing power you need, etc. but more options are only a good thing. Remember that the 'T' in IoT doesn't just mean little things - these guys are talking about devices that monitor large transformers and power distribution equipment (critical electrical infrastructure). It's likely that an IoT device for that would be doing a lot more than, say, a smart meter for a home for which Linux probably would be overkill.

nomoch 10y ago
The problem I have with that is that I hear it every decade about niche-x. And people are right, but as soon as costs drop enough that niche-x can support the full desktop stack there's now a niche-y where you're still stuck with hundreds of bytes of memory, the market is x10 as big, and you're using the same tools you were using a decade ago. An 8-bit micro controller will be with us forever because it is the smallest computer that is useful for more than trivial tasks, it will just keep getting smaller and smaller. I won't be surprised if the first space ship to land on a different solar system has trillions of 8-bit computers on it the size of atoms.
gchadwick 10y ago
> It's only a matter of time before that kind of RAM size is normal for very low-power and low-cost devices though Really? SRAM isn't cheap and takes power, DRAM cheaper (especially once process/packaging technology means you can place it on the same die or in the same package as the processor) but still costs power. Fundamentally if you want very low-power you're gonna go for lowest RAM possible. Ditching it is an easy way to save power. Even if RAM is cheap using 1/32th of it (8mb vs 256k) makes things cheaper still. Important if you're going for very low-cost.
- rjsw 10y ago
  Once you go outside the size of RAM chips that are used in mass-market devices the cost goes up by a lot.

Avshalom 10y ago

They built it for high assurance applications where being able to review absolutely everything from ground is important foremost. IoT is just an application the cpu is also well suited for.