A BitScope owner recently suggested that because BitScope is now compatible with Raspberry Pi why not build an entire electronic projects lab around it?
This made sense so we thought we'd give it a try using our first BitScope Ed project Breadboard One.
We've based it on BitScope Mini so everything can be powered by the Raspberry Pi itself (we're low power here!). If you need more juice, just plug in a powered USB hub. BitScope can supply between 200mA and 500mA to the circuit via its Smart Port Interface if it's connected via sufficiently powerful USB hub. We like this hardware hack if you want a neat setup!
The only other things you'll need are a keyboard, mouse and monitor. We used a cheap Logitech wireless keyboard/mouse combo ($ 20) and a 1080p HDMI monitor which was otherwise gathering dust in the corner of the office. Of course you don't need such a big monitor, BitScope software will work on a screen as small as 1024x768 so anything VGA compatible with one of these will do.
Next we cracked open another Raspberry Pi (we love them around here :-) and installed Raspbian and BitScope DSO using NOOBS (we recommend this technique, it's much easier than burning your own SD image).
When the download and install was complete we started BitScope DSO and voila, we have all the waveforms captured from the Breadboard One project using a BitScope Mini all of which is powered and controlled from the Raspberry Pi. Impressive!
Now it's important to note that Raspberry Pi is not the fastest little computer on the planet but for this application it's fast enough to get the job done. At its default size you can expect a display refresh rate of about 5Hz for a logic display, 3Hz for an analog display or 2Hz for a mixed display (analog and logic) with special features like phosphor decay and waveform parameter tracking turned off.
If you switch to full-screen (1080p in our case, as shown here) these frame rates slow by a factor of about two but it sure looks good on the big screen!
Of course for one-shot capture, which is what you're more likely to do with a project like this, frame rates are somewhat moot; the result appears very quickly. We'll work through our BitScope Ed posts as we publish them using this setup to see what issues arise using Raspberry Pi for this sort of project. If you've got a BitScope and a Raspberry Pi let us know how you go!