0xCAFEBABE & 0xFEEDFACE (2003)

If you're a child of the 80's in North America it does!

(Do a google search on the number, without the 0x0 prefix...)

It's a reference to a song ("867-5309 / Jenny") by Tommy Tutone. It's pretty dated by now.

Dated?!

DATED?!

BLASPHEMY!

;-)

Semi-related story with some insider baseball:

There are quite a few memorable words you can spell using 32 or 64 bits—like BA5EBA11. This is the story of me -not- choosing one of those.

These bit-pattern words are handy because they’re easy to recognize, especially in a random memory dump.

On my first “real” assignment, I was writing real-time embedded C code for a 16-bit processor that communicated with a host microprocessor on a server. We needed to run periodic assurance tests across a bus to ensure reliable communication with the host since we weren't constantly using the bus.*

We were given an unused register address on the host processor and told to write whatever we wanted to it. The idea was to periodically write a value, read it back, and if we encountered any write errors, incorrect reads, or failures, we’d declare a comm error and degrade the system in a controlled manner.

Instead of using zeros or something like 0xDEADBEEF, I decided to write 0x4D494B45 - "MIKE" in ASCII. It was unique, unlikely to be tampered with, it worked, and no one argued with me. The code shipped, the product shipped, and all was well. We even detected legitimate hardware errors, which I thought was pretty cool.

Fast forward two generations of systems, and long after I’d moved on from that team, the code had been ported around but that assurance test remained unchanged. Everything was fine until they brought up a new generation of systems, flipped on the firmware for that device, and 10 seconds later, my assurance test clobbered an important register. The entire system promptly checkstopped and crashed. It took the team days to figure out what was wrong, and I had to explain myself when they found "MIKE" staring back at them from the memory dump.

That was a fun project. ;-)

* Note: It would've been bad if our device went out to lunch because we were responsible for energy management of the server. If the power budget was exceeded and we couldn't downclock and downvolt the processor, something might have crashed or been damaged.

Not just that, but they also wrote the numbers in decimal - they didn't even want them in the code as an example of what not to do.

Maybe someone was having too much fun and got carried away, but what an odd sense of humor.