Author Topic: Need Help with Arduino Uno Sketch to Create ASCII Characters  (Read 18178 times)

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Offline Dago

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Re: Need Help with Arduino Uno Sketch to Create ASCII Characters
« Reply #50 on: April 21, 2014, 07:04:03 am »
I get the notion of the baud rate.... why does the frequency measurement not give the same result as the counter?  Thanks

The frequency counter is "counting edges" and baud is not the same thing as frequency. If the symbol has a lot of zeros then the frequency will be lower because there is less edges... makes sense?
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Offline David_AVD

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Re: Need Help with Arduino Uno Sketch to Create ASCII Characters
« Reply #51 on: April 21, 2014, 07:24:15 am »
I get the notion of the baud rate.... why does the frequency measurement not give the same result as the counter?  Thanks

The frequency counter is "counting edges" and baud is not the same thing as frequency. If the symbol has a lot of zeros then the frequency will be lower because there is less edges... makes sense?

Well, lots of adjacent ones and zeros anyway.  All ones and all zeros will have the fewest edges.
 

Offline Electro FanTopic starter

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Re: Need Help with Arduino Uno Sketch to Create ASCII Characters
« Reply #52 on: April 21, 2014, 11:23:16 pm »
What happened to...
...have the ability to generate test signals that are effectively ASCII characters while having control over the amplitude and pulse durations and maybe the underlying clock frequency on which the pulses ride.

Hi SL4P,

Thanks for reminding us of all that - without a doubt those are still objectives within the overall goal.  Given the feedback here I'm working on all the "easy" :) parts first but I'd like to get back to - or move on to - a solution that would give fuller control of the various waveform attributes.  I'm open to any suggestions on how to do it all including gaining control over the amplitude and pulse durations and the underlying clock frequency (especially on a bit by bit basis in addition to a byte by byte basis).

Seems to me there should be some beginner's curriculum somewhere that covers Ohm's Law, Power Supplies, the ability to create and manage waveform voltage (amplitude), frequency, pulse durations, etc. using an oscilloscope in a way that teaches A-D, decoding, etc. - maybe with Arduino hardware and software, etc. - something that would help beginners put a few key concepts together.  I'm sure there is a class out there but in the meantime it gives us all something to discuss which gives us a combination of this  :palm:, that  |O, and the next thing  :box:, and sometimes this  :-DD, and hopefully this overall:   :-+

EF
« Last Edit: April 21, 2014, 11:29:56 pm by Electro Fan »
 

Offline Electro FanTopic starter

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Re: Need Help with Arduino Uno Sketch to Create ASCII Characters
« Reply #53 on: April 21, 2014, 11:47:23 pm »
I get the notion of the baud rate.... why does the frequency measurement not give the same result as the counter?  Thanks

The frequency counter is "counting edges" and baud is not the same thing as frequency. If the symbol has a lot of zeros then the frequency will be lower because there is less edges... makes sense?

I know  :palm:

Ok, I get that edge counts will vary depending on the particular character combinations (and the associated transitions) of 1s and 0s - and therefore any frequency counter or measurement based on edge counts will vary. No problem.

But just to clarify, the display in the upper right hand corner is what I'm referring to as "the counter" (I think that's what Rigol calls it).  Is this display in the upper right hand corner showing the frequency of edge counts (or something else)?

Along the bottom of the scope display is another measurement (which is where various measurements can be selected and placed) showing "frequency" - what is this display showing (what frequency is it measuring), and why does it vary so much?

Seems to me that given the frequency variation on the bottom measurement that it is more likely to be showing frequency based on edge counts (since it varies so much), and the counter at the top is more likely to measure the clock frequency since it seems to be much more stable - but hey, that's why this is the Beginner Forum.   :)

Thanks, EF
 
« Last Edit: April 22, 2014, 12:00:32 am by Electro Fan »
 

Offline SL4P

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Re: Need Help with Arduino Uno Sketch to Create ASCII Characters
« Reply #54 on: April 22, 2014, 01:01:52 am »
ElectroFan - where do you live?
I'm in forced semi-retirement (health), and have plenty of time to explore this over coffee.
Cheers
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