Have you ever wondered how to make sense of hexdumps?

e1a02000e5d00000 e3500000012fff1e
e3a00000e2800001 e7d23000e3530000
1afffffbe12fff1e

Or been curious to know what exactly does a bxeq lr instruction mean in assembly?

If so, then you should sign up for the introduction to assembly programming and reverse engineering class. You can learn assembly programming and machine architecture using reverse engineering techniques on your own code. In this class we will write code, compile it into an executable and then disassemble it to learn about registers, stacks, branches, function calls and argument passing, structs and other common idioms.

Experience with any programming language is required; the examples in the class with be in C, with dissassembly into ARM assembly. Bring your own laptop with arm-elf-gcc and associated binutils installed to follow along.

I’ve been inspired by the Lasersaur project to try building an XY table for laser cutting, Makerbotting, and light duty milling. The brackets, motor mounts and carriages are all 3D printed on NYCR’s Makerbot Thing-o-matic. Today I was able to put most of the pieces together for a dry fitting and found a few bugs — the carriages have too much play and will bind if pulled from the side, so the pull-pull belts will need to be moved to the inside of the rails, which will require all the carriages to be redesigned. The good news is that the printed teeth to engage the belt are well positioned to secure the belt under the rails without any additional hardware.

One of NYCR’s most popular weekly events is Lunar Laser Mondays using our Epilog mini-35 laser cutter. The only supported system is Windows with CorelDRAW and Epilog’s closed source driver, which doesn’t seem right for a hackerspace. Luckily, AS220 Labs has figured out how to talk to the Epilog using PJL. I’ve written a command line tool, epilog, that will translate the Postscript file into commands for the cutter.
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I’m tired of my keys always jangling in my pocket, so I built a key-multi-tool out of a Crank Brother’s M5 bicycle tool. While I had the tool disassembled, I rearranged it so that the M3, M4 and #2 phillips were on the same side, which leaves room for five keys on the other side. It turns out other people had the the same idea. My keys still need cutting down since the key heads on the Medco keys are so large.

Inspired by Ranjit’s instrument-a-day (Make coverage), I’m writing a new wrist watch face every day for my progamable inPulse watch (more background). The full sources are posted online for others to build on.

Day 1 was a fixed point 3D rendering engine with a rotating Utah Teapot, day 2 was a rolling odometer or aviation altitude ticker display and day 3 is a 24-hour analog clock. This last one still needs some work.