Ever wanted to see how well your oscilloscope adheres to its stated capabilities? What if you buy a new scope and need a quick way to test it lest one of its channels its broken, like [Paul Wasserman] had happen to him? Now you only need a Pi Pico and a few extra components to make a scope test board with a large variety of signals it can output, thanks to [Paul]’s Sig Gen Pi Pico firmware.
Despite the name it’s not a signal generator as we know it, as it’s not flexible in the signals it generates. Instead, it creates a dozen signals at more or less the same time — from square waves of various frequencies and duty cycles, to a PWM-driven DAC driving eight different waveforms, to Manchester-encoded data I2C/SPI/UART transfers for all your protocol decoder testing.
Everything is open source under the BSD 3-Clause license, and there’s even two PDFs with documentation and a user manual, not to mention the waveform screenshots for your own reference.
It’s seriously impressive how many features [Paul] has fit into a single firmware. Thanks to his work, whenever you have some test equipment in need of being tested, just grab your Pico and a few passive components.
A long time ago…… in a more civilized age, before the dark times…. Tek marketing would actually send you a little circuit board powered by a 9volt battery. The board would generate multiple waveforms that could be measured on their scopes. It demonstrated the measurement capabilities of their high end scopes.
Well put.
In ancient times I would drag out my 545 with built in calibrator and ramp outputs….
I like it and I dont like it. – First, seams neat. Second seams useless. I can all this with the gear on my bench. But ok, what about the average person wanting to get into electronics? Simple, save up a bit more money and buy a scope from reputable manufacture, say Rigol DHO800, and yes, save your money, I dont want to hear about its expensive when it cost less than an iPhone. This tool may have had a place yesteryear, but does it really today? – but then im sure some HAD fanboy will say its greatest thing since sliced bread
> I dont want to hear about its expensive when it cost less than an iPhone
An iPhone *is* expensive for quite a lot of people around the world.
Hell, an iPhone is expensive for what you get!
Every tool is expensive for what you get if you don’t know how to use it.
“You’re holding it wrong”
Yup, for some people an iPhone costs similar to salary on two months.
It would be useful to carry around if you are trying to buy something at a swapmeet/hamfest.
yes, and it’s also wonderful for someone who’s got a cheap scope (maybe even a digital one) and a spare Pico, and wants to know how far they can get with it, test out protocol decoding and all that! Personally, I know that I now want to test that one Bitscope I have laying around, and this firmware will help a ton with that.
>Simple, save up a bit more money and buy a scope from reputable manufacture
people like you are why kids and anyone with a dollar less in their pocket than you avoid any kind of electronics hobby. good for you, you can afford a “real” scope. there are boat loads of good used analog scopes to be had for well under $100 at fests, flea markets, etc. with a cheap tool like the one in the article you could at least tell if the bargain scope worked. while I may not want to fly on a plane or be subjected to a medical device that was designed using only a garage sale scope, for a hobby user on a budget a decent tek scope from the 80s opens a world of possibilities. if everyone you know has a $1k phone I wouldn’t expect this argument to make sense.
People like you are why I don’t read comments that start with “people like you”.
The difference between fooling around and science is repeatable proof. Your trust in the price tag of a manufacturer is honourable but nowhere near scientific.
Don’t diss an iPhone! Just because it’s an overpriced gadget for gullible people in need of poorly designed status symbol doesn’t make it a bad smartphone. It’s smarter than its users…
I saved a bit of money and bought new Siglent SDS1104X-U. Then I wrote a review for it, got paid, saved a bit more money and bought Owon XDM3051 multimeter. And then I’ve got lucky and bought an 2x80MHZ AWG used, for half the price…
This Pico generator is worse than one I bought from China few years ago, that uses a FPGA and R2R ladder. If someone wants a good quality generator for testing, one can build it the proper analog way: a Vackář oscillator paired with PLL for easy frequency stability and adjustment. For low frequencies just make an RC oscillator or use NE555…
And if someone really, really needs an uC, there are these cheap modules with AD9833 and AD9850. Just add some better filters and buffer…
Michael Bradley said: “I dont want to hear about its expensive when it cost less than an iPhone.”
Michael, you obviously do not know how over-priced and closed Apple products are. Also, there’s the debatable issue of who actually makes iProducts – Political Prisoners, Children, Slaves? Google/Alphabet isn’t much better. They harvest your life and sell it to others.
The “Necessary” Hardware Problem:
The problem is these days, a person must have a mobile phone because banks, et-cetera all REQUIRE two-factor authentication. So now I can’t even do banking or pay bills without a mobile phone that is chained to two-factor authentication. So now, I never carry the phone with me, it’s too risky. What happens if I lose the mobile phone or it is stolen? I’m completely screwed! My life is controlled by that phone due to mandatory two-factor authentication. And no. Having some sort of backup like and Email address is never enough for these control freaks.
Every time I leave home intentionally without my mobile phone because I’m scared to lose it, I imagine the phone sitting on the kitchen table with a huge chain that wants to be tied to my neck due to two factor authentication. “Something You Know PLUS Something You Have” was from the beginning a failed concept.
+1
This is exactly what I want from Hackaday. It is useful, educational, well documented and not cost prohibitive. Excellent work and I thank [Paul Wasserman] for taking the time and effort to share it.
How about an Oscilloscope built from a Raspberry Pi Pico? https://how2electronics.com/diy-smartphone-oscilloscope-using-raspberry-pi-pico/
Nice! Pitty it only works on Android. With a Pico-W it might be possible to do this over Wifi or Bluetooth perhaps
If the creator [Paul Wasserman] is reading this: your sentence “The quick brown fox jumped over the lazy dog” does not have an ‘s’ in it! Try “jumps” or “dogs”. I used the same sentence for years before I realised!
Thanks for the feedback. I have used that sentence many times and not noticed the missing s
A couple of years ago, I ran across a tweet from 2018 in which @JackOfQuills suggested that the sentence, “Sphinx of black quartz, judge my vow” was “objectively a million times cooler” as a sentence containing all 26 letters.
The proper sentence is: “the quick brown fox jumped over the lazy dogs back”, and there’s your “S”
Nice signal generator project with minimal parts.
I don’t really need it to test a scope but looks good for a stand alone signal source that can be slapped together pretty quickly.