Software Engineering

19 articles

Remarkable

"Space... the final frontier" is how the pre-recorded message from NASA to the Crew of Discovery started this morning. This afternoon while covering the final departure of Discovery from the ISS, the Newsman said "Remarkable - a remarkable bit of technology and a lasting mark on history" - or something to that effect. I thought "Remarkable" - that's a word…

Radioactive Telepresence

How timely!  A couple of months ago the discussion started - "will unmanned vehicles make a transition into civilian use".  I've been taking the stance that since we're talking vehicles - not just aircraft but all forms of non-stationary robot, that it is inevitable.  Even with aircraft I believe it is inevitable, though it may take a little longer for…

Quit Bugging Me: Making Maps

A tool commonly used in embedded debugging is a linker map - a map of where all the symbols are in the runtime image.  These maps are useful as they turn raw addresses reported by some exception stubs (etc) into offsets into the data or text (program routines) in the computer's RAM.  They give you an idea of what may…

More Bacon: increasing science return

In a recent blog I wrote, Bringing Back The Science Bacon,  one of the things I talk about is increasing the science returns of a mission by doing some data processing on the mission robot, before it sends back information.  If a computer has the ability, and the trade-offs gathering data, processing it into information, available computer throughput and bandwidth…

Quit Bugging Me: Revalidated

One day, I get this phone call.  "We're working with the system, we see the calls that update the exception handlers early on - connecting the clock routines, etc.  Then not very much farther on we see the system has run past where tasking should be running but it's not.  When we check, we're not getting any clock interrupts, and…

Do you design flight software?

Normally I don't like this blog to sound like a marketing microphone, BUT... once in a while something comes along that's Worth It.  I'll keep it short and sweet.Next month, Larry Kinnan will be running a web presentation about how VxWorks 653 OS is used in the Boeing 787 Dreamliner.   Click here for more information. I've learned a lot from Larry…

Sand Trap

Spirit Rover is heading to her sixth anniversary on Mars, but it looks like she'll have to sit the dance out.  Spirit has been trapped, basically high-centered on a hard spot surrounded with flour-like soil.  Some surprising test results show that one of the wheels we thought was jammed has some slight function, but the bad news is one of…

Bit Rot Amnesia

Spirit Rover has been having a number of problems recently, anomalous behaviors, losing contact with Earth, even forgetting commands.  Amnesia has been one of the larger concerns.At the heart of this issue is a bank of flash memory.  Flash pretty much works by saturating cells to "1"s, then writing the cells that need to be 0's.  "quantum wells" hold the charge…

Quit Bugging Me: ABI

What's in an ABI?  An Application Binary Interface is a lot like a API - Applications Programming Interface, except instead of just telling you how to make a call, what parameters to provide, and what returns and errnos to expect, an ABI also tells you something about how the interfaces work.  Understanding an ABI for a CPU means you understand…