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  1. Replies
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    Merry Christmas

    Merry Christmas everyone.
  2. Thread: Potato Chips

    by wastrix
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    Re: Potato Chips

    Looks pretty suspect to me, they only have an eBay store, and as far as I know there aren't any reputable places selling these. To get those kind of speeds you'd have to use some quite advanced...
  3. Thread: MOSFET failure

    by wastrix
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    Re: MOSFET failure

    Thanks for the replies.

    I'll get some of the controllers and test exactly what happens at the supply rails and FET terminals during power on/off.

    The FET drivers are supplied by a 12V rail...
  4. Thread: MOSFET failure

    by wastrix
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    Re: MOSFET failure

    Sorry, I forgot to put it on the schematic above but I actually do have large schottkys reverse biased across D-S of all the FETs to reduce the strain on the body diode, and I also switch the MOSFETs...
  5. Thread: MOSFET failure

    by wastrix
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    MOSFET failure

    Hi All,

    I recently experience a catastrophic failure mode on some H bridge motor controllers. The controllers are designed to run at 48V, 20A continuous. The project had four controllers, each...
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    Re: Starting out with ARM Processors

    The STM32F4 discovery board is another option if you want to try an M4 very cheaply.
  7. Re: Difference Between USART(16Fxxx) & EUSART(18Fxxx)

    Have you looked at the serial output with a digital oscilloscope or logic analyser to verify that they actually are producing the same signal at the correct baud rate? I suspect this might be a...
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    Re: Favorite Solder wick / desoldering braid

    I think anything with a brand name will be fine. Chemtools and Multicore are often considered "the best" but probably not a lot in it.

    I do have some really bad solder wick, it doesn't work much...
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    Re: Faze Hot Plate Clone

    Well don't blame us when it latches up and sets the building on fire!
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    Re: Protn 24 upgrade cost

    I'd be happy to buy it at that price.
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    Re: New features in the compiler!

    This looks very interesting! I'll have to play around with it later.
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    Re: Strange behaviour using vars with Delayus

    What are your fuses? Does it make a difference where the wordvar is in memory?
  13. Re: PICKit2 clone - hex file and device type transfer from Proton.

    Have you selected the new directory in which PK2CMD resides in the install new programmer wizard?
  14. Re: PICKit2 clone - hex file and device type transfer from Proton.

    Can you make it work by typing the command into the command prompt manually? Are there any error messages?
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    Re: Eliminating gang error

    The issue with the dual pot is that for mechanical reasons (length must be greater than 25mm, I spent ages finding a suitable part), the only available type is the 10k type I mentioned.
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    Re: Eliminating gang error

    Thanks for your replies.

    @David, those pots are not great, but they're about as good as I can get my hands on for a reasonable price. I tried them out today and performance was pretty marginal as...
  17. Re: PICKit2 clone - hex file and device type transfer from Proton.

    Assuming you're using PK2CMD, try this: pk2cmd -PPIC$target-device$ -F$hex-filename$ -E -M -J -H1 -R

    The PK2CMD app itself will tell you the full list of arguments. I know -Hx specifies to leave...
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    Eliminating gang error

    Hi all,

    I have to smoothly adjust the amplitude of a wideband (DC-50MHz or so) signal from 0 to full scale, but at the same time know what position my adjustment is at. The simplest solution is to...
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    Re: Tiny stepper motor.

    All optical media players AFAIK use dynamic focusing, the plastic actually warps and wobbles very significantly when spinning and the laser must be focused very precisely to get high data density. In...
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    Re: Pic Crazy! 12F1501

    It only changes the firmware when switching device families, e.g. 16F->18F.

    I do find it freezes sometimes (particularly after hibernating the PC), this is solved simply by unplugging and...
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    Re: Rotational power calculation

    If I understand your situation, the motor needs enough power to spin up the load in the required time (here you can consider the kinetic energy of the mass rotating at full speed), and power to...
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    Re: Calculate speed BLDC motor

    Have you tested under load? You must test the system under load.
  23. Thread: Connecting ADC

    by wastrix
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    Re: Connecting ADC

    It is not good, and could cause permanent damage if you leave it like this for a while, but if you accidentally set it up wrong for a few seconds it's very unlikely that anything will be damaged. The...
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    Re: Calculate speed BLDC motor

    I think I would tighten the RC filter also.

    Also, make sure you run your scope at maximum sample rate, on peak detect mode. On the first shot you have quite a lot of noise and could potentially...
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    Re: Calculate speed BLDC motor

    You are using the hall sensors to commutate the motor as well as measure speed, right?

    I think that rather than trying to add a delay or filter or something to the hall sensor code you should...
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    Re: Calculate speed BLDC motor

    Can you see the false triggering of the hall sensors on a scope? If they are false triggering for some reason, then the motor will not be commutating properly either. Perhaps it is being caused by...
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    Poll: Re: Recycle old equipment /components

    I can get ISA motherboards a dime a dozen at the local e-recycling place!
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    Re: New tool: USB HID Description Wizard

    Great utility! I have published the article.
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    Re: Rounding a float (fround?)

    You have to split it up:

    float_revs=10.23
    test_revs=float_revs * 4
    test_revs=fRound(test_revs) / 4
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    Re: Rounding a float (fround?)

    I think I see what you are trying to do...

    Why not do something like:

    output = fRound(input * 4) / 4

    (input and output are floats)
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    [SOLVED !] Re: Adding a +, "like" or "thumbs up" feature

    I'm not sure if you've seen the "I found this post helpful" button.

    But I agree it would be a good idea to have a thanks or like button like on many other forums, which would be a bit more general...
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    Re: One of my products on TV

    Very impressive!
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    Re: MOSFET Switching - PWM

    Are you using the same FET with the arduino?
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    Re: Strain Gauge measurement

    Hi Ken and whoever else that may be interested,

    The 4 layer boards turned out nicely. I haven't assembled them yet but they look fine and I have tested for shorts on some of the closer traces and...
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    Re: 12f683 simple voltmeter

    Yes this will work fine.

    10k/3.3k gives you a division factor of (10+3.3)/3.3 = 4.03, so if you multiply by 4 in the firmware it will always read slightly low. If you want improved accuracy, you...
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