Just like publishing a book and going to print, passing your Gerber files to a PCB assembly house usually results in days and days of checking everything is correct, pushing the button, and immediately finding an error somewhere when it gets back. Kind of makes you wonder what the fuck you were doing during those hours and hours of checking!
I had been holding off pressing the button on this one due to the pathetic level of the NZ$, getting 2 of these baby’s assembled at JLPCB worked out at NZ$230 including exorbitant courier fees which I again I assume are because of our lousy exchange rate. Great for exporters and tourists, alas, not for me! Anyway, long story short, here is the board fresh back from the assembly house, and looking like a charm.
Of course, plugging the USB power cable into it did nothing, no led, no smoke, no loud pops, nothing! Actually I don’t usually mind fixing these easy faults, generally no brain required, but, and note to future self on naming nets, VBUS and 5V on a simple board like this are very likely the same net!
OK. So one very dodgy blob of solder later, we now have the VBUS and 5V nets connected.
Plugging the board in this time lit the LED, brought up the RP2350 boot loader, and mounted a drive on my laptop. Woohoo! I decided to use PicoMite to do the testing as it proved to be nice and straightforward to work with last time. I dropped the latest PicoMite uf2 firmware image onto the drive, and it copied over fine, then rebooted.
Unfortunately after the reboot I should have had a standard config PicoMite board running, but no, the boot-loader came up again, and Linux again saw the board as a USB drive. (sigh!)
This usually means the image (uf2 file) was broken, or a hardware problem between the RP3250 and the Flash Memory. Unfortunately it also of course means I have to some some real digging, with logic analyzers and the debug probe, which also means going in the unheated workshop in the middle of winter.
This might take some time! – groan!
Schematic Here for those that want to see if they can find the problem before me.
