My Workplace, in a Vignette
I work at The Dini Group, a small company in downtown La Jolla. We build FPGA boards (Xilinx and some Altera) to support logic emulation & ASIC prototyping.
Yesterday I was testing my third board design. It’s a revision of one of our older boards, generally cleaned up, and ready to go into a production environment for a contract client. The board has a security-related purpose, and it will store private keys. Consequently, one of the customer’s requirements was that to the extent possible there should be no unnecessary I/O paths, and still required paths should be disguised.
We use USB to bring up and configure the boards, but we couldn’t just put a USB plug. So instead we put in a four pin header like this one. V+, D-, D+, G, in a row.
Next challenge: We needed a cable to connect that to a computer. We could buy one for a few bucks… but Neal and I came up with a better idea.
- Get a USB A-to-A cable, the kind that aren’t supposed to exist. Dave had one in his drawer.
- Plug one side into the computer and the other side into one of the USB back-panel bracket that come with most motherboards these days. We have one in every dead computer in the Dungeon, and most folks didn’t bother installing them on our last batch of computer purchases.
- And those header blocks on the end of the bracket’s cable plug directly into the board header pins.
Cost: zero. Results: excellent! (Pics: soon.)
Yesterday we found ourselves in need of a second cable. This time I just took a six-foot A-to-B cable, snipped it near the B end, snipped the header block off a second bracket, and soldered the connections up. I think for version 3.0, I’ll use heatshrink instead of masking tape.
This isn’t a particularly abnormal day.
A few more pictures of my desk:
- Picture the First - Phone, sharpie, multimeter probe, tea cup, board under test, PCI extender to power DUT, Nalgene, keyboard for Linux machine under desk, Subway sandwich for afternoon, paper plate that used to have bagel, mouse for Linux computer, power supply for test, SMA cable, edge of main machine
- Picture the Second - other side of main (WinXP) machine, solder sample boards, partly-assembled PSX board, post-it with a few part numbers scribbled on it, set of low-ohm resistors soldered in parallel from an old old power supply capacity test, ASUS motherboard box, some instrument that was on my desk the first day and I’ve never touched, Dave’s trashcan
- Picture the Third - behind me: schematics, schematics, and more schematics, box with new hard drive for backup server (oops I need to install that), Gigabyte motherboard box, headphones, ethernet hub under desk, miscellaneous cbles (power, ethernet, usb, serial) along back of desk
November 11th, 2007 at 2:34 am
wow. but where’s your amp?
November 13th, 2007 at 9:02 pm
Mentioning the hardware for the Linux machine to distract from the blue taskbar with the green Start button on the monitor – clever.
(Sorry, had to.)
December 2nd, 2007 at 2:02 am
For some reason, dunno why exactly, my RSS feed for you just stopped working and I had no idea you were still posting! GAH! Awesome pictures btw, I had no idea you were into that sort of thing (also, even though I had very little idea as to what you were actually talking about, I enjoyed the above story about board design and USB shenanigans).