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Parallax Propeller, why is it so overlooked?

rwgast

So the parallax propeller is a 32bit 8 core micro. It is what I learned to electronics/embedded coding with! Its basically like having 8 AVR chips in one and never needing an interrupt. Currently im taking the time to learn PASM or Propeller Assembly. I curious as to why there aren't more of these out in the wild? Im also learning ARM and would one day like to switch from electrical to embedded as a career.... but I feel like I am wasting my time with this chip even though its great especially for industrial and robotics multitasking at the bear metal level. I never see a propeller chip in a job discretion or in a product. To me the prop is very close to a software defined CPLD as is maybe the XMOS.

 

What do you all think about the propeller chip?

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  • The Propeller chip is unpopular for so may reasons: it is very limited compared with ARM Cortex and far from cheap.

     

    The 8 processor model is difficult to design with and this puts people off but there are worse features to come - each processor has a very limited amount of memory (512 words is tiny) and access to a bigger common memory (still only a tiny 8k words) is time sliced and so very slow. The next big issue is that the chip has effectively no on-chip peripherals. A typical cheap ARM Cortex will have SPI, I2C, UARTS, timers, USB etc etc.

    Several companies have attempted to dump peripherals and code them all in software - it's never popular because it's hard work and difficult to support in practice and always gives worse performance than dedicated peripheral functions. XMOS are currently plowing this furrow and have found a few niche applications but aren't breaking into the mainstream (they've inherited too much attitude from Inmos so I don't think they ever will make the big time.)

     

    So while the Propeller is interesting, and can give good performance if you get a job that is a really good fit, it isn't  a patch on general purpose micros for general purpose jobs - and they make up most of the market. For niche stuff DSPs are much better at DSP, FPGAs are much better at massively // and can be clocked so much faster etc etc.

     

    So right now I can buy an ARM Cortex with a 180MHz clock 1Mbyte Flash, >192kBytes RAM, on chip USB, Ethernet, Encryption/Decryption etc etc for about the same price - the Propeller just doesn't offer anything expect less stuff and more hassle.

     

    MK

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  • The Propeller chip is unpopular for so may reasons: it is very limited compared with ARM Cortex and far from cheap.

     

    The 8 processor model is difficult to design with and this puts people off but there are worse features to come - each processor has a very limited amount of memory (512 words is tiny) and access to a bigger common memory (still only a tiny 8k words) is time sliced and so very slow. The next big issue is that the chip has effectively no on-chip peripherals. A typical cheap ARM Cortex will have SPI, I2C, UARTS, timers, USB etc etc.

    Several companies have attempted to dump peripherals and code them all in software - it's never popular because it's hard work and difficult to support in practice and always gives worse performance than dedicated peripheral functions. XMOS are currently plowing this furrow and have found a few niche applications but aren't breaking into the mainstream (they've inherited too much attitude from Inmos so I don't think they ever will make the big time.)

     

    So while the Propeller is interesting, and can give good performance if you get a job that is a really good fit, it isn't  a patch on general purpose micros for general purpose jobs - and they make up most of the market. For niche stuff DSPs are much better at DSP, FPGAs are much better at massively // and can be clocked so much faster etc etc.

     

    So right now I can buy an ARM Cortex with a 180MHz clock 1Mbyte Flash, >192kBytes RAM, on chip USB, Ethernet, Encryption/Decryption etc etc for about the same price - the Propeller just doesn't offer anything expect less stuff and more hassle.

     

    MK

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  • in reply to michaelkellett

    So right now I can buy an ARM Cortex with a 180MHz clock 1Mbyte Flash, >192kBytes RAM, on chip USB, Ethernet, Encryption/Decryption etc etc for about the same price - the Propeller just doesn't offer anything expect less stuff and more hassle.

    .. and run a propeller emulation on it with 1:1 speed (probably - I am guessing here)

     

    Several companies have attempted to dump peripherals and code them all in software - it's never popular because it's hard work and difficult to support in practice and always gives worse performance than dedicated peripheral functions.

    Performance should not be an issue, at least not for statdard perpiphals (SPI, PWM, UART, I2C ...) those are all simple protocols. Indeed simple enough to implement them whith a few gates in hardware... that's how they were designed.