Would the Daisy hardware allow to implement an oscilloscope, to view waveforms?
Older STM32 MCU were used for entry-level oscilloscopes. H7 has new ADC with 16bit resolution and various other improvements. It certainly should be usable.
Thanks! Are fast screen operations to draw lines and shift the screen to the left supported/exposed, or would we need to extend libDaisy/DaisySP etc? Are the examples for fast line drawing etc? (I’m new to the platform)
DaisySP doesn’t deal with graphics, it’s only used for audio. I guess there are still interesting use cases for DSP processing if you want to be able to view spectrogram as well as waveform.
There is code for driving display in libDaisy (see hid_oled_display.h and its’ cpp file), but it’s written for specific display model that would be too small for oscilloscope.
STM32 provides “touchGFX” library that includes hardware acceleration, but I’m not familiar with it.
Thanks, just a small display is fine (Hemisphere for Ornament&Crime shows a scope on the half side of its screen).
Oh. Somehow I thought you were considering making an actual daisy-based oscilloscope. Ok, if you only meant previewing audio waveforms that Daisy generates, it’s fairly trivial. libDaisy has necessary routines for rendering on display and ring buffer for storing data, you’d just need to combine that.
How do those differ? Isn’t previewing an audio waveform a simple form of an oscilloscope? The Korg Minilogue has such oscilloscope. https://youtu.be/l_dSaz4agAQ?t=182
Of course this is not going to replace my Rigol DS1074 for other electronics work.
Yeah, I’ve meant engineering oscilloscope. The difference would be signal bandwidth that it can measure.
I can recommend the small OPEN SMART TFT displays, available in sizes from 2" to 3.5" with and without touch. I’ve driven them over SPI from STM32H103 based ‘Blue Pills’ so the H750 based Daisy should manage it with its eyes closed.
Example supplier here but also available on eBay, etc.
I wrote a thread about Scope-O-Matic (an arduino based oscilloscope) a few weeks ago (be it in a different forum) and as a wave form display with a small oled display it works really nice!
Nice idea ! Looks like there’s almost room for two displays and two inputs ? Did you consider using Arduino on a Blue Pill for a bit more memory ?
Originally the scope is suitable for measurements but in my use case seeing a waveform was sufficient. I thought of adding a second channel, but haven’t looked into it yet. Have a look at the radiopench blog for the original setup. I merely implemented this design and changed the way information is displayed on the oled screen. Oh yes, and I added a bit of circuitry to be able to display AC voltages.