ALASKAN BULL WORM! Jumperless V5 PSRAM Mod Kit

8 megabytes of extra room for activities!

Do PCB assembly crimes in the process!

The Jumperless V5's RP2350B has 520kB of RAM, which is pretty awesome for a microcontroller. But in the course of scope-creeping JumperlOS into a full blown operating system, there have been certain features that I've found are only really possible with more (fast) memory to work with.

Things like having an onboard logic analyzer are really only constrained by how much memory you have and how quickly you can write to it. So capture rates and sample depth are directly determined by how much RAM it has available (I did some crazy stuff with DMA ping-pong buffers to get JulseView kinda working without the extra RAM, but it was never stable enough to consider it a real feature.)

The biggest benefit here is to give the onboard MicroPython interpreter a ton of room for activities and do all its behind-the-scenes magic to run huge scripts. 

Idk, I'm constantly writing new firmware updates so there will be a bunch of cool features coming out in the future that'll need this extra RAM to work. 

Don't read this as some paywalled cash grab, Jumperless V5 was designed within a week of the RP2350 coming out, before there was really much mention of PSRAM support as a new feature (I hereby blame Paul Beech from Pimoroni for not breaking his NDA on the RP2350 with Raspberry Pi while we got drunk together at Teardown 2024), I would have just put a PSRAM chip on the Jumperless V5 and wouldn't need to go through all this trouble to squeeze out some extra performance. The files are here, and you can totally just send these off to JLCPCB and make it yourself, or just dead-bug a PSRAM chip off a PGA2350 like I'm doing right now before the boards arrive. 


Anyway, the boards aren't in yet (there are already config flags and some support in the firmware) and with a mild delay due to Chinese New Year, they'll probably be ready to ship sometime in early March. I'm taking preorders with a 20% discount to help pay for manufacturing, but you're also welcome to wait.

Installation

This thing is mildly tricky to install, but if you own a soldering iron, this is absolutely doable in ~30 minutes. I will include some excellent solder wick, solder, and some alcohol prep pads for removing the flux. Worst case, if you fuck it up so badly that you break something, the infinite warranty on your Jumperless V5 means you can just let me know and I'll arrange shipping for your Jumperless and PRSAM mod kit back to me, and I'll send it back installed, tested, and ready to go for no charge. 

If you order a Jumperless V5 from me and a mod kit in the same cart, I'll assume you want it pre-installed and just do it for you unless you say otherwise.

Return service means I'll email you a shipping label, you print it out and use it to ship me your Jumperless, then I'll install the mod and ship it back. (Yes, you could save some money by trying it yourself, possibly breaking something, then using my free repairs policy to have me do it for you, and I actually prefer you go that route because I believe in you.)




This test is showing that PSRAM is still ~4x slower for reads and ~9x slower for writes, but there's a ton of it and it's still hundreds of times faster than writing to flash.



For people who didn't grow up watching Spongebob, this is the reference: