This is a guest post by by Norm Jackson, co-founder of Thort Werx.
Most of us start in electronics with a multimeter, and that takes us a long way. Sooner or later, though, you need to see what a signal is doing over time: a PWM output that won’t dim an LED properly, a sensor that reads correctly on the bench but incorrectly in the project, or a serial line that goes quiet. That’s the moment you need an oscilloscope and a logic analyser, and it’s usually the moment the budget says no.
Picotronix is our answer to that. It’s a modular oscilloscope and logic analyser, based on two Raspberry Pi Pico 2 units (a Pico 2 and a Pico 2 W), made by Thort Werx, a small Australian company based in Sydney and on the Gold Coast. You start with one Main Module and add plug-in picoPods only when a job needs them. It goes to Kickstarter soon, and Peter kindly offered us this space to explain what it is and how a beginner would use it.
The Picotronix Main Module and expansion picoPods
The Main Module on its own is a two-channel digital storage oscilloscope, an eight-channel logic analyser and a frequency meter, with a 320 × 240 colour LCD and three expansion ports. The Pico 2 handles signal capture; the Pico 2 W runs the display and controls and can link to a PC or phone. Both Picos sit in sockets, so you can see exactly what’s inside.
The picoPods plug into those three ports and add the capabilities a particular job needs:
- Analog: Precision analogue inputs.
- Differential: Differential inputs for measuring across a component rather than relative to ground.
- Waveform generator: A 12-bit signal source, so you can feed a signal into a circuit as well as measure it.
- 12-channel logic: Logic capture at up to 150 MSPS, with up to 14 logic channels in total.
- ADC-100: Dual 100 MSPS ADCs, supporting capture at up to 75 MSPS on one channel or 50 MSPS on both, with the RP2350 running at its stock 150 MHz.
- Electronix Lab: A teaching pod, described below.
The idea is simple: a beginner buys the Main Module, and the instrument grows as their projects do, instead of paying upfront for a do-everything box.
Circuit boards designed with KiCad (naturally)
The project’s circuit boards were designed with KiCad. If you want to learn how to design PCBs with KiCad, checkout out Peter’s KiCad Like a Pro course and book series, now in its fifth edition.
First steps on the bench
Here’s the kind of thing a reader of this blog could do in their first hour, using an Arduino or ESP32 sketch they already have.
- Look at a PWM signal. Load a sketch that fades an LED using analogWrite. Clip a probe to the PWM pin and the ground lead to GND, then choose the oscilloscope from the on-screen menu. You’ll see the square wave, and the frequency meter will show its frequency. Change the duty cycle in the sketch and watch the pulse width change on screen. This is the moment PWM stops being an abstract idea.
- Compare two signals. Put channel 2 on the LED side of the current-limiting resistor. Now you can see the drive signal and the signal at the LED, side by side.
- Watch a serial line. Switch to the logic analyser and connect the logic inputs to the I²C or UART signals you want to inspect. Seeing the start of a transmission, the gaps and the idle state explains a lot of “Why isn’t my sensor answering?” problems. For I²C at the usual 100 or 400 kHz, set the capture rate to 1–4 MS/s: enough to see the individual bits while retaining a capture long enough to observe whole transactions. On-screen decoding of the bits into bytes is part of the software being rolled out in stages.
- Plug in a picoPod. When you plug in a picoPod, Picotronix recognises it, and the display shows what it is and how to set it up. You spend your time on the circuit, not the menus.
None of these steps needs a computer.
For teachers: the Electronix Lab picoPod
Electronix Lab is a picoPod made for teaching. It connects to Picotronix by cable and uses all three expansion ports. Students set up logic on the pod, the pod turns that logic into a real signal, and they see the result straight away on the Picotronix display. Change the logic, and the waveform changes in front of them: cause and effect on the same bench.
We’re also building guided experiments. Picotronix, or a computer connected to it, can be loaded with experiment setups that configure the instrument and walk a student through each step: making the connections, choosing the mode and range, taking the measurement and making sense of the result. The hardware is built and working, and the guided-experiment software is being developed in stages. We’d welcome ideas from teachers on which experiments to develop first.
Because the Pico 2 W can stream captures to a PC, a teacher can put a live capture on a big screen while students follow along on their own units.
Open and programmable in MicroPython
If you’ve taken one of Peter’s MicroPython courses, this part will feel familiar. Picotronix is programmable in MicroPython, with direct access to the RP2350’s PIO state machines and 12 buffered, protected I/O lines. That means you can write your own virtual instrument, script a repeatable test or design your own picoPod for a job we never thought of. The ports are open, so a pod doesn’t even have to be a measuring tool.
Picogram, the protocol the two Picos use to communicate, is also designed to link Picotronix to a PC or phone. It allows measurements to be shared in a form an AI could work with directly: taking a capture, explaining what it shows and suggesting the next test point. The capability is here; the software is being developed in stages.
Where Picotronix fits on the bench
Picotronix won’t replace a high-end bench oscilloscope, and it isn’t trying to. It’s built to be the first real instrument on a learner’s bench and a handy second instrument on an experienced maker’s: small enough to take to a project, open enough to adapt and able to grow one picoPod at a time.
Follow the Picotronix project
The hardware is built and working, and Picotronix is launching on Kickstarter soon. Visit the Picotronix project homepage to follow the project. You’ll also find a four-minute overview and a 21-minute bench walkthrough there.
Thanks to Peter for the invitation. We’re happy to answer questions in the comments.
Norm Jackson is co-founder of Thort Werx, an Australian technology company based in Sydney and on the Gold Coast.