Setting up the Logic Analyzer

Well, after putting the analyzer back together, I had to clone the HD before I used it (I didn’t want to disturb anything on the drive by even powering it up first).   You’d think this would be a simple project…. but oooh no.

Let me recount the fail and eventual success.

First things first, I removed the drive from the analyzer almost as soon as I got it.  I put in a junk 4.3 gig SCSI drive of similar form factor so I could play around with the analyzer.  I plug a keyboard I had laying around in, and an IBM mouse I had.   I fire up the analyzer and it’s working fine.  When powered on the analyzer will show a black screen, then about 15 seconds later it changes the scan rate, then the numlock LED on the keyboard lights, another 5 seconds of black screen and the boot screen appears.

It’s unhappy about the harddrive not being formatted how it would like it, but otherwise it’s fine.  I try to boot of the CDROM, which is done by typing BO <some other stuff> to BOot the machine.  Well, the B key on the keyboard doesn’t work!  I tried to enter it using the alt-numpad trick.. nope this isn’t a PC so that doesn’t work.  I take the keyboard apart, and trace the membrane.  Turns out there’s some microcracks in about 5 or 6 traces on the membrane… it’s unfixable so I extract the little tiny PCB and cable for use later and chuck the balance.

Because my keyboard is dead and I don’t have another, I decide that it’s time to go into work to pick up another from our computer “boneyard”.  One Dell PS2 keyboard later, I’m back to try my luck again.  Plug it into the analyzer… fire it up… and nothing!!  Screen stays black, LED on keyboard never lights.  The keyboard works, I was using it earlier on another machine.

After trying to boot it several more times, I am wondering if I somehow broke it or if somehow it’s not happy with the keyboard.  So I grab the pcb and wire from the dead one and plug it in and turn it back on.  This time the analyzer boots just fine and turns the numlock LED on, so I plug the Dell keyboard back in and turn it on.  Nothing.  Sooo, it doesn’t like the keyboard.  Great.


I figured at this point it’d be a good idea to clone that harddrive.  So I plug it all in, as seen in the picture above.  After burning an Ubuntu Rescue Remix CD, I pop it into the CDROM on the machine, start it up and it says “Booting from CD…”  then nothing.  The drive’s light illuminates, the motor starts, disc spins… then nothing.   5 more reboots confirm that it is not going to work.  My friend figures it could be the BIOS being so ancient is preventing the CD from booting, and I agreed.  No problem, we’ll just update its 1998 BIOS to a more modern one last modified in 2004.

Get out the floppy disks, download the bios, pop the disk into the drive, click “my computer”… and hey, the A drive is missing!  Greeeat, this machine’s floppy is dead and the other machine with a floppy drive is currently dressed like a deer with its guts hanging out, and in no condition to boot into its usual OS.

The solution is to email the bios file to work (After renaming the zip file, because Gmail does not allow exe’s even in ZIP files. grrrrr), then drive in and write it to two floppies.  I do not trust the data halflife of the 3.5 inch floppy disk.  Several times the disk fails to read properly and I’m stuck trying to copy data onto another to give it another try.  Fast forward to work- I got my floppy in the drive, hit a: in DOS and the drive makes very unhappy “I can’t even find the directory” sounds.  great.  “Abort, Retry, Fail?”  I pop in another floppy, and the same thing.  A third also results in the message and accompanying clunks and groans from the drive.  At this point I was wishing there was a “Pee in Drive Door” option to the fail prompt.

This means yet another trip to the “boneyard” to harvest a hopefully working 3.5″ drive to put into this machine.  A suitable donor was found, and it was grafted into place, and the machine rebooted.  THIS drive was liking my disks a bit better, and I managed to write the files I needed onto them.  I also changed out the Dell keyboard for a more ancient PS2 keyboard with the larger full size DIN and a converter to get it down to the smaller mini-DIN that computers use these days.  Great.

Rushing back home, I try the keyboard on the analyzer… It works! great!  That’s one more problem out of my hair.  So, I plug the keyboard and its adapter into my test machine, plug the mouse… uh… PLUG THE MOUSE… DAMNIT!  nope.  I cannot plug the mouse in:  The adapter and the mouse’s overmolded ferrite bead is interfering and I cannot plug both in at the same time.   I briefly thought about hitting the ferrite with a hammer then cutting the overmolded plastic off to extract the shattered ceramic but decided against it.  Turns out I don’t need the mouse anyways.  Mice are for wusses.

Going keyboard only, I pop in my floppy disk and boot into DOS and run the BIOS flashing program.  Amusingly, this goes without incident.  No problems.  I check the new BIOS to make sure the boot order is CD first, and it is.  Hitting reset, after putting my Rescue Remix in the drive, and waiting for the SCSI card’s gyrations, the drive spins up and I hear seeking! joy!  But it was not to be.

“image checksum error, sorrx… <symbol>
boot fahled: press a key to retsy…”

“fahled”?  “retsy”? “sorrx”?  What was this black magic appearing on my monitor?!  I am mad I didn’t take a picture of this, it would’ve been nicer.  But anyways, I reboot 3 more times and get some variation of the above.  On examination of the errors, they are all “off by one” errors- “sorry” vs. “sorrx” and so on- each wrong character has an issue with D0.  So, as can be seen in the above picture (waay up there), I have a second CDROM drive sitting on top of the machine.

After replacing the drive, it boots! Rescue Remix is loading, which takes a long time.  It gets through to the end nearly and then croaks.  ClamAV (who ordered up virus scanning? I didn’t) is whining that there isn’t enough RAM to load itself.  Great.  I had 128 megs in there, which apparently wasn’t enough.  So I rummage around and find another 64 megs and pop it in and reboot.  It does the same thing.  greeeat.  After more rummaging, I cannot find anything else except a 256M stick that has my writing on it: “BAD” it says…  Well when I wrote that I was having other issues with the machine so maybe it wasn’t so bad after all?

Plug the possibly bad RAM in, boot it up and run memtest86+.  After letting it gyrate and jitterbug on the RAM for 20-30 minutes, I deemed it good and rebooted into Rescue Remix.  So far so good- it is not whining about clamAV being out of memory any more.  A command line! Great!  After doing some Linuxy things to mount the dump drive the data’s going to, a quick run of ddrescue gets me copying my junky 4.3 gig test drive to the 20 gig IDE drive.

Well, it’s copying but the drive definitely sounds very unhappy.   In fact, it sounds like a coffee grinder someone threw pebbles in!  Terrible grinding and buzzing noises.  They appear to be coming from the head actuator, though, and it seems to be reading.  After it was all said and done, there were 8 unreadable sectors.  I didn’t care though, this was the dry run and a test to see if everything would work.  Turns out it did.  The drive had hiphop MP3s on it, as I found out.  I dunno who put them on there or where they came from though, the drive was given to me ages ago.

Elated that it finally is working, I power down and swap in the analyzer’s drive and fire back up.  After the 3-4 minute bootup, the prompt appears.  Unfortunately it is also locked up!  After 3 or 4 more cycles of this, I start mashing the keyboard as it’s getting ready to drop me to the command line and whatever I did worked (or the phase of the moon was just right)-  the command line is open for business.


Woot! It’s copying!!! The copy goes absolutely uneventful, except for a minor flub at first that caused it to start copying the drive to a RAMdisk.  This got the full 20Mbyte/second until it filled up.  Whoops.  Copying to the proper destination was a bit slower, somewhere around 5Mbyte/second which is the maximum rate for that drive apparently (an old 20 gig IDE one).  The copy goes by and I take the drive out and put it back in the analyzer.  It only took me the better part of a day to do this.


YEAY! It’s booting! And it likes my ancient keyboard!  I had to blow away the root password and make another, and I poked around a little in the file system, then rebooted it and let it load and start up the main application.


Yeay, that works.  I have to log in as root at this point since I am unsure about how else to do it.  I think there’s a default user named “logic” but I haven’t read up about it.  At this point, the GUI starts and we’re poking around in it.  There’s just one problem.  The mouse is not working.  GRRRR.  Nope, it doesn’t like the damn mouse either!  After getting into a CLI window and poking around, I tried to start DOOM.  Yes, this logic analyzer ships with DOOM from the friggin’ factory!!  I find it and try to launch it but it whines and won’t start.  At this point I shut it down and tried some other mice.  I had two more mice and it liked the second one (an old Microsoft ball mouse).


WOOT! SUCCESS!  It likes the mouse, and I start up DOOM and play a few levels!  Excelllent.  I wonder how many engineers were playing DOOM instead of debugging circuits?  The world may never know.  This sure beats the “Bugs” (a “Centipede” clone) easter egg game on my HP scope!  Oh yeah, I checked out the rest of the analyzer and everything seems to be in good shape, so I am ready to use it!

More updates as I get to that point.