What is it?

Jumperless V5 lets you prototype like a nerdy wizard who can see electricity and conjure jumpers with a magic wand. It’s an Integrated Development Environment (IDE) for hardware, with an analog-by-nature RP2350B-based dev board, a drawer full of wires, and a workbench full of test equipment (including a power supply, a multimeter, an oscilloscope, a function generator, and a logic analyzer) all crammed inside a breadboard.

You can connect any point to any other using software-defined jumpers, so the four individually programmable ±8 V power supplies; ten GPIOs; and seven management channels for voltage, current, and resistance can all be connected anywhere on the breadboard or the Arduino Nano header. RGB LEDs under each hole turn the breadboard itself into a display that provides real-time information about whatever’s happening in your circuit.

It's not just about being too lazy to plug in some jumpers. With software controlled wiring, the circuit itself is now scriptable, which opens up a world of infinite crazy new things you could never do on a regular breadboard. Have a script try out every combination of parts until it does what you want (à la evolvable hardware), automatically switch around audio effects on the fly, characterize some unknown chip with the part numbers sanded off, or don't bother with any of that and just play Doom on it.

But more likely, you'll be using it to get circuits from your brain into hardware with so little friction it feels like you're just thinking them into existence. So yeah, wizard shit.

What are these Variant options?

No production process has a 100% success rate, and being a crazy perfectionist means I have a bunch of these with minor cosmetic defects you will never see, or ones I had to do some repairs on. All of these should be functionally and aesthetically perfect, they're just outliers, which I felt should go to people who want a Jumperless with some personality.

Hardware Refurbished

Means I had to swap out a chip or LED that wasn't working from the factory. It's been fixed and thoroughly tested, and the exact repair I did is marked on the box. But this thing was not designed for easy hand assembly so there's a tiny but nonzero chance of something going wrong in the future. I use leaded solder for all repairs so these aren't RoHS.

Production Proof

This was the last revision right before full-scale production. It's a revision above what the beta testers have, but I changed one tiny thing in the crossbar routing after this (specifically, the location of ROUTABLE_BUFFER_IN is switched with ROUTABLE_BUFFER_OUT). The firmware has a persistent flag so it knows this and routes accordingly. It shouldn't really make any difference in normal operation, you just need to remember to set the revision again (if you run a full flash nuke (regular firmware updates or even a factory reset don't require any special handling.)

This is hardware revision 4, not to be confused with the generation, which was the exact nonsense I was trying to avoid when skipping Jumperless V2-V4, yet here we are.

Perfect

Means I was probably just being dumb when packing these and mistakenly flagged it as defective. This is a regular production unit, except more thoroughly tested while trying to figure out why it ended up in the rejects pile. It usually was just a faulty probe cable before I realized they needed to be tested.

Rev 7

This is a super minor change to the hardware in this latest batch, I added friction-fit OLED headers on the main board so you don't need to use the SBC adapter board to connect a screen. It's connected to the internal I2C bus, so if you wanted, you could use it to add new stuff to you Jumperless's hardware. The 0.91" OLED is included.