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    Working for me on Firefox 77.0.1 and Chrome...

    Working for me on Firefox 77.0.1 and Chrome 85.0.4183.102 on MacOS.
  2. As you've discovered you can't use a quadrature...

    As you've discovered you can't use a quadrature encoder library to count pulses on a single pin, as
    quadrature requires both signals to change to go round the state transition diagram. If only one...
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    Assume its small, a few mA. This is a very...

    Assume its small, a few mA. This is a very complex chip with loads of I/O pad drivers, so they will be physically
    very small on the die, and thus not able to handle much continuous current without...
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    My code copies the data out to process it - if...

    My code copies the data out to process it - if you want to alter the original block you need to
    make sure you've got it in write mode to start with, and in that case you can avoid copying and
    just...
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    Pointer type casting is compile-time operation,...

    Pointer type casting is compile-time operation, nothing actually happens at runtime, its the same bits.
  6. An external ADC with separate analog and digital...

    An external ADC with separate analog and digital supply pins is recommended to get clean readings - internal ADC on
    a complex processor chip are always a compromize in performance (but often very...
  7. The first AudioStream object to be initialized in...

    The first AudioStream object to be initialized in the code that is capable of driving the update mechanism will be the one
    selected to do it, so make sure the AudioOutputI2S dummy object occurs...
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    Then it might be worth having a go - the...

    Then it might be worth having a go - the processor is obviously gone, but its possible other things have followed.

    With a BGA package I suggest finding some video tutorials - in theory you remove...
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    Do you have a hot-air rework station?

    Do you have a hot-air rework station?
  10. I would suggest using uint16_t for 16 bit...

    I would suggest using uint16_t for 16 bit unsigned int, int16_t for signed 16 bit int, etc etc. And you'll have
    to check endianness too - you might need to write marshalling/unmarshalling code if...
  11. Reckon this is the mistake: if (new_value2

    Reckon this is the mistake:


    if (new_value2 < min_value1) min_value2 = new_value2;
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    Yes Teensy's run off USB power. LiPo batteries...

    Yes Teensy's run off USB power.

    LiPo batteries are not 5V. Thus you need either 2S into a voltage regulator to make 5V, or 1S into a boost-converter to
    make 5V.

    I recommend using a...
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    Note that %2d or %.2d as a format string doesn't...

    Note that %2d or %.2d as a format string doesn't limit the length of its expansion to 2 characters. So allocate
    enough characters in the buffer for the largest integer plus a few more - even if...
  14. If you want to strengthen the pull-ups from 10k...

    If you want to strengthen the pull-ups from 10k to 5k, all you need to do is piggy-back extra 10k resistors on top of
    (and thus in parallel with) the existing pull-ups on the PCB. This is easier...
  15. I need a circuit diagram to understand this...

    I need a circuit diagram to understand this fully. When asking a technical question you need to be much less vague:

    "I have a stand alone 4 LED driver" - no part number, no datasheet, nothing to...
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    AES blocks are 16 byte, default audio lib blocks...

    AES blocks are 16 byte, default audio lib blocks are 256 byte, so process 16 AES blocks per audio lib block.
    So something along the lines of:


    uint8_t * bptr = (uint8_t*) (block->data) ; //...
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    Datasheet links? I need to know the _full_ tech...

    Datasheet links? I need to know the _full_ tech specs, not just part numbers, in order to see what's what. In particular
    motors are often available with multiple winding versions, and this is what...
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    Why any inaccuracy? Single-sample granularity is...

    Why any inaccuracy? Single-sample granularity is just a case of returning the sample number for each timestamp,
    or you can generate a click on a generated click-track stream to provide...
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    128, you have not changed anything. AudioMemory...

    128, you have not changed anything. AudioMemory takes the number of _blocks_ to pre-allocate space for.

    The samples per block is set by this code in AudioStream.h:


    #ifndef...
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    Power supply and stepper motor details are...

    Power supply and stepper motor details are useful, can you provide this?

    Also how long are the ribbon cables?
  21. MIDI isn't designed for timing that accurate. ...

    MIDI isn't designed for timing that accurate. You'd expect MIDI latencies to be measured in milliseconds, not microseconds.
    You'd be at the mercy of the receiving software as to what happens, but...
  22. Thread: Phase Shift PWM?

    by MarkT
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    You'd need to configure 4 separate timers for...

    You'd need to configure 4 separate timers for that (usually each timer controls multiple PWM pins). Depends on
    the precise microcontroller how to do this.

    But perhaps you just need decent...
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    Probably a lack of power or of bulk decoupling on...

    Probably a lack of power or of bulk decoupling on the LED supply - I make it 4A peak needed for 66 of
    those RGB leds, so the supply and decoupling needs to be up to the heavy load they pose and the...
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    When I write quadrature encoder code I use the...

    When I write quadrature encoder code I use the invalid transitions to increment an error count, not
    the position count. Then you can programmatically check for errors if you suspect you are not...
  25. Opamps don't usually break if you short the...

    Opamps don't usually break if you short the outputs or set them up to duel, they are designed to current-limit internally
    and indefinitely. 100 ohms or so is usually used on the outputs to prevent...
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    asm is the way to go really - updates to the...

    asm is the way to go really - updates to the compiler or selecting different optimization level wlll screw up
    the hand-selected C code approach.

    Having said that if the clock speed is alterable...
  27. An opamp buffer would provide a much lower output...

    An opamp buffer would provide a much lower output impedance, useful for driving long cables for instance.

    Low power opamps aren't great for audio, they have much higher distortion at high audio...
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    This thread may be useful:...

    This thread may be useful: https://forum.pjrc.com/threads/48417-Voltage-limit-on-Teensy-3-6-for-RTC-Vbat
  29. FP gives 8 more guard bits and no...

    FP gives 8 more guard bits and no saturation/wraparound issues (till the final output), its the right solution
    if you have hardware support for floats I think, otherwise 32 bit fixed point might be...
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    The values depend on the frequency, those values...

    The values depend on the frequency, those values don't work down to the frequency you're using. Add a resistor in series with the input
    pin too so that it won't be driven over or undervoltage too...
  31. There are no compound values passed as arguments...

    There are no compound values passed as arguments or results in C or C++, everything is a simple numeric/character/
    bool type or a pointer. So arrays cannot be passed by value, nor structs or...
  32. p isn't global, its nuked every time through the...

    p isn't global, its nuked every time through the loop() function.

    If something has to hold state across multiple function calls it must be global in extent.
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    The datasheet will say, but not enough with heavy...

    The datasheet will say, but not enough with heavy currents being switched on the same supply - separate supply is
    really going to help, as may some more decoupling, and attention to current paths to...
  34. Its just an I2C interface to program a bunch of...

    Its just an I2C interface to program a bunch of registers from what I can see - although there are interrupts you can also use if you want,
    but I suspect you just need an I2C library.

    It won't...
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    I normally code an algorithm up initially in...

    I normally code an algorithm up initially in Python and can use all the nice tools/libraries like matplotlib.pyplot
    and scipy.signal (super useful this one for DSP, everything Matlab has but...
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    Put AudioProcessorUsageMaxReset() in setup(),...

    Put AudioProcessorUsageMaxReset() in setup(), and then you can print out debugging
    using AudioProcessorUsage() and AudioProcessorUsageMax()
  37. Well maybe - its a compromise between protection...

    Well maybe - its a compromise between protection and transition speed - depends on the capacitance
    being driven.
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    In that case write both your counter and another...

    In that case write both your counter and another counter (or timestamp) that always increases, so that you can
    tell which is the latest position written.
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    Do you have a link to the datasheet for this...

    Do you have a link to the datasheet for this encoder?
  40. Indeed - the resistors also serve as protection...

    Indeed - the resistors also serve as protection should a servo fail with its supply shorted to the input pin. Somewhat higher value like 4k7 might be
    even better for this.
  41. The code in wiring.h is long map(T _x, A...

    The code in wiring.h is

    long map(T _x, A _in_min, B _in_max, C _out_min, D _out_max, typename std::enable_if<std::is_integral<T>::value >::type* = 0)
    {
    long x = _x, in_min = _in_min, in_max =...
  42. Most logic inputs don't pull DC current(*), only...

    Most logic inputs don't pull DC current(*), only transient spikes for a few nanoseconds.

    Some servos may not be using standard logic gates though, and might take some current - this is something...
  43. Vocoding normally just adds formants, which is a...

    Vocoding normally just adds formants, which is a stack of tunable resonant filters, not a change in pitch of the signal itself.
  44. Hammond style vibrato/chorus via circuit simulation

    I wanted to improve the accuracy of my vibrato/chorus for my Hammond organ MIDI synth code, as its
    a distinctive part of the sound. (Note this is separate from the Leslie rotating speaker effect...
  45. Audio ADCs and DACs typically may not support...

    Audio ADCs and DACs typically may not support dynamically changing sample rates, requiring quartz-stable
    clocking to get good results - they often have clock-speed detection circuits to switch in...
  46. The AudioSynthWaveform class limits frequency to...

    The AudioSynthWaveform class limits frequency to Nyquist, so if the audio sample rate is set higher it will allow higher frequencies,
    just checked the code:



    void frequency(float freq) {...
  47. I suspect this is because there's no simple easy...

    I suspect this is because there's no simple easy way to do this for an arbitrary rate-conversion - the technically
    ideal way requires sinc-pulse summation (band-limited pulses) which is very to...
  48. That would be meaningless at 44100 sample rate as...

    That would be meaningless at 44100 sample rate as +23kHz = -21.4kHz, and unless you are handling complex (ie quadrature) signals
    negative and positive frequencies are indistinguishable. So going...
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    The Due and the Teensy both have through-hole...

    The Due and the Teensy both have through-hole micro USB sockets, meaning the steel body has 4 tabs that are soldered into
    plated through holes in the PCB, which is as good as you'll get (although I...
  50. Shifting a new pattern in is not the same as...

    Shifting a new pattern in is not the same as shifting in reverse... I think we were at odds because you happened
    to be shifting in a shifting pattern to a set of shift registers. With non-latched...
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