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Paid propeller programming work - stepper motor controller — Parallax Forums

Paid propeller programming work - stepper motor controller

ekettenburgekettenburg Posts: 4
edited 2015-07-21 18:44 in Propeller 1
Please excuse (and remove this post) if help wanted/contract work is not allowed to be posted here - I found some other similar posts, so I'm guessing it might be OK - but my apologies if not.
I am working on a project using a Propeller MCU - the circuit design is complete and I've dabbled in SPIN and used some items from the Obex (Very cool!) - I am well versed in embedded programming but find myself short on time for the learning curve of the Propeller (for now at least), especially given what I want to achieve with it.
I posted this job on Elance, but received almost no replies from anyone who had ever used a Propeller - so here I am!
The job:We are looking for someone who is familiar with both Propeller MCU and C# programming to implement a Stepper Motor controller (7 motors) with GPIO and other features (I2C and WS2812 LEDs) that are controlled via UART messages from a C# application. We are looking for someone to handle the Propeller and (preferably) C# programming (just a demo of the UART between the two) only, not to build a prototype or do any design work.

I think this is a very straightforward job with the two tricky parts being:1. Implementing configurable S-curve acceleration for driving the steppers. (NOTE: the steppers are being driven by external stepper drivers, the Propeller only needs to produce STEP and DIR signals)2. Figuring the best way to implement UART, I2C, WS2812, and signals for 7 steppers all in one Prop while maintaining very high baud rates (230400 minimum, but 460800 or higher strongly desired) and step rates. (NOTE: Since writing the requirements I've found the linked serial module is probably not sufficient for this speed, so an alternative is probably needed).
THIS JOB HAS BEEN AWARDED - thank you all!


Comments

  • Peter JakackiPeter Jakacki Posts: 10,193
    edited 2015-07-16 02:28
    Sounds interesting, but unfortunately I would implement this in Tachyon Forth and it would include a high-speed communications channel up to 2M baud with built in command and script interpreter.  All the rest except for some S-curve perhaps is already implemented or straightforward enough.

  • Cluso99Cluso99 Posts: 18,069
    Posting here has been acceptable previously, and I haven't heard about any changes.

    There are some faster uart drivers. Look for the faster multi port serial driver in the obex.
    For getting the serial running, you will get plenty of free help here.

  • DavidZemonDavidZemon Posts: 2,973
    edited 2015-07-16 02:58
    I'd love to apply for this job. I'm afraid I have no C# experience, but I'm a quick learner and already well versed in C++ and Java, so C# shouldn't be a tough challenge.
    If you'd like to see samples of my work, look no further than PropWare.
    If you take me on for the job, the Propeller code will be entirely C++ with snippets of inline assembly as used in PropWare. Unless you object, I would also use PropWare for the build system.
    High-baud serial communication won't be an issue - PropWare's built-in UART object can do bursts of 4.4 Mbaud writes and I think it was 2.7 MBaud reads. Full specifications for speed can be found here.
  • Question about the project:
    Will any part of it be open-sourced after completion?
  • I'm really open to any language, build system, etc - as long as it is well commented and I can build on Windows without too much pain (CMake is just fine). 
    C++ would be great - I already know it so that would make it much easier for me to read.
    The C# side really isn't 100% needed - I've written the entire program this will interact with in C# - the reason I asked for a demo is to understand how the Propeller board will expect me to send things like LONGs based on how the programmer implements the protocol/parser. If someone can just provide adequate documentation for that, so I can implement it in C# myself - that's fine and the time savings would be welcome. 
    Great to hear high serial speeds should not be an issue! 2MBaud would be awesome - thats what my Uart to USB chip maxes out at.
    Open Source: This is a closed source project at the moment. That said, the protocol (not that it would be much use to someone else) and resulting motor control setup (aside from any libraries that are already open of course) are the two things that would need to remain closed, at least for now (though if someone wants to offer a discounted rate if it is open sourced, I'd be open to it). Any of the UART, WS2812, I2C stuff can be licensed any way the programmer wants, as long as the license allows for close sourced commercial usage. 
    Thank you all - if anyone wants to offer a estimate for the job please PM or use Elance - I'd love to get it started ASAP.
    @Cluso99 - thanks for confirmation that it should be OK to post here!

  • Your comments regarding C# are promising. Sounds like you'd rather I not learn C# if I don't already know it, so I'll plan on skipping that part.
    Before I submit a proposal I'm going to work on PropWare's installation. Right now, it's one of the key weak-points and I second-guessing myself on whether I'd feel good about using it for a paid project. Hopefully I'll have something more stable tonight or tomorrow and then I'll look into submitting something to you.
  • Yes - I'm more than happy to do the C# side as long as I'm given a good definition of what serial data to expect/send to/from the propeller.
    Don't be afraid to use PropWare just because the installation isn't smooth - I can work on any platform and am very used to having to build things on obscure linux distros, so a complex installation for the build enviro is just fine. It sounds like PropWare has some very promising performance (plus I like the idea of C++ so I can read it) so I'd love to hear a bid from you if you are interested.
    Thanks,Erik
  • Try these guys at easterline  research and design. I think they charge $100-$150 per hr.
  • Esterline
  • Proposal submitted via PM
  • Thanks everyone for the tips and proposals - this just has been awarded.
    Thanks,
    Erik
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