Embedded PC Troubleshooting

It’s not uncommon among broadcast equipment that it contains a small off-the-shelf embedded PC, often running Linux.

It’s also not uncommon that the equipment will just up and die one day for no seemingly good reason, however, while the reason is a maddeningly silly one— it’s easy to get it running again!

So here’s the most common one I run into. This is on an SSL (Solid State Logic) NetBridge, which is part of their system that— well, I’ll admit I have no clue what it does.

The problem: After unplugging the box and plugging it back in, it never started up right. A front panel LCD lit up and indicated something weird like it was waiting for connection to the host, but never did anything beyond that point.

Remove about 64 screws aaaaaand…

VIA Mini-ITX motherboard

Believe it or not… nothing too special here. This is an off the shelf VIA Mini-ITX platform motherboard. If you had to, you could track down a replacement entirely. The RAM is just standard RAM, so if it went bad you could swap it. I forget what’s on the other end of that ATA cable but it was probably a CompactFlash card in an adapter.

Now, look under that multiport serial card’s corner. See the coin cell battery standing at attention in the vertical holder? Well, it was more like… a dead parrot nailed to its perch.

You can just see one wire connected to the header for the front panel LEDs and buttons. In this case I think it was on the reset pin. There is nothing on the power switch pins.

The way this box left the factory, it was configured to expect that it would never actually shut down. It was expected that the box would just lose power, and the BIOS settings were set to “resume after power failure”. Worked fine until… the battery died and the settings went byebye.

 

The fix was simple: Open the box, connect a keyboard and monitor, short the pins on the front panel header for “power button” to wake the board up, enter the BIOS settings and configure them appropriately, then put all 64 screws back in the thing.

 

I dunno, maybe it wasn’t actually 64, but it was a LOT, man.

 

I’ve seen the same kind of setup used also with a capacitor across the power button pins as described in this car PC article; a certain type of satellite receiver used in radio stations (I forget the make/model!) and the Comrex Access rackmount units used this as well. I believe on those it was more a backup measure to ensure the box still started if the settings got lost, though.

 

It probably wouldn’t hurt to keep a spare motherboard around for these units. In some cases the software is very dependent of the hardware being JUST so. In advanced and, frankly, ridiculous cases, the software may have a license key linked to the MAC address of the onboard network card, and you may have to swap a surface mount serial EEPROM. (a pox on your house to anyone who implements this…!!!!)

Also, any easily removable storage device may be backed up for future recovery if needed. My usual solution is to just take an image of the whole drive from a Linux system. You’ll probably have to do these as root.
sudo dd if=/dev/sdx of=backupFile.img to create the file (insert appropriate device node of course)
sudo dd if=backupFile.img of=/dev/sdx to restore it (contents of the device will be overwritten!)
If you use a similar size or larger media as the replacement, it should work fine – I’ve never seen anything care that blocks exist beyond where the partition map says they do.

One star review.

Not surprising or amusing: getting cockplugged in traffic.

Surprising and amusing: getting trapped indefinitely on a closed road in front of an escape room.

https://youtu.be/L7jnk2mv3PU

One star review. Was not pleased with the experience.

The Ends of the Line

I just traced it out and these are the limits of how far you can go in Southeast Florida by public transit.

Other possible odd destinations are possible, such as South Bay, Canal Point, and Indiantown, but by distance, this seems to be the maximum.

Yes, this is plotting highway distance– Google does not have route information for some of the bus lines, so it cannot do a public transit trip plan automatically.

Transit routes used:

Key West Transit / Lower Keys Shuttle

Miami-Dade Transit / 300 Dade-Monroe Express -> Busway Flyer -> Metrorail

Tri-Rail / Northbound train to Mangonia Park station

Palm Tran / Route 21 northbound -> Gardens Mall

Martin County Transit / Route 20x -> route 1

Treasure Coast Connection / route 1 -> route 7

GoLine route 6 -> route 11

From here there is a 16 mile gap before you would reach the Space Coast Area Transit system. The rural city of Micco does not appear to have any public transit. If this DID connect, the northern limit would be Aurantia Road and US1 in Mims.

Do not attempt this trip unless you are insane.

It would likely take multiple days and one of the routes is only available weekday commuter hours.

The Harris HPX adventure

It’s big. It’s highly efficient, for a tube rig. It can do analog and HD. It runs the damn lowest stack temperature I’ve ever seen. It’s full of Linux. It has… a curiously labelled hidden pushbutton I’m amused and scared of. It confused so many other engineers they called me in to shape it up! It’s… the Harris Broadcast HPX! (GatesAir branded, nowadays.)

And it inspired me to invent…. transmitterwave

This post is very image heavy so I’ll split it to avoid an endless front page on my blog.

The HPX.

Remember when the following tag was <lj-cut text=”Read more…”>? Pepperidge Farm remembers.

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Troublesome Meta Substances.

There are a few substances you should watch out for in the electronics field. No, I’m not talking about lead, not even about beryllium…

  • Unobtainium. This is a substance only really rumoured to exist, yet it’s often the base material for parts in something you’re working on. Nobody can find it now, but there’s always someone, maybe you, who knew where to find the Unobtainium parts… 25 years ago in a tiny shop that’s long gone and replaced by a check cashing store. Unobtainium is known to exist in all three states of matter, but once it becomes gas, it irretrievably escapes ….
A jar of pure Unobtainium, liquid form.
  • Expensivium. While it can be obtained, its scientific purpose is totally unknown. However, Expensivium is the most maddeningly, frightening thing to find as part of an electronic part, for its presence means that these parts will be subject to wild increases in price whenever you need them. Expensivium is usually added to the composition of semiconductors that have been on the market a few years, rf power transistors, high voltage capacitors, wire and cable.
  • Chineseium. A very inexpensive but disappointing element, it has often been unsuccessfully used as a substitute for Expensivium and Unobtainium. Parts based on excessive amounts of Chineseium will usually fail very quickly due to this material dissipating right out of existence. Attempts to refill a system with lost Chineseium will not theoretically work, as in the theories on refilling lost Magic Smoke, for the high concentration of Chineseium will just lead to even more rapid failure.

While Unobtainium, Expensivium, and Chineseium are not directly toxic or harmful to persons, their presence is associated with a scientifically vague yet statistically proven link to migraine headaches and anxiety.

Shenzhen’s Finest

I have a love-hate relationship with the businesses in Shenzhen, China.

On the upside (actually downside?) they are THE one and only place where most electronics come from in the world now.

On the downside it’s a city of thieves and bullshit artists.

Nice try

I laughed upon this arriving. It was supposed to be a black bodysuit I was going to use as the (lazy) beginnings of a Chat Noir costume. What they sent was a tiny envelope with two silicone rubber bands in it.

Since it was an eBay purchase, I’m about 99.9% sure eBay will side with me if the seller balks at a refund. Still, WAFWOT: what a flipping waste of time

true horror.

Today, I witnessed something I’ve never seen before, and something that horrified me.

 

Trump Tower lobby (Miguel Mendez)

I walked into our news control room at work as the satellite feeds were all set up on a vacant podium in the lobby of Trump Tower.

 

We were a few pages* into the newscast when Trump walked out and prepared to speak.

 

The reaction in the room was one of collective disgust, fear, and anger.

 

The fact that we have a “leader” that can universally invoke that is just staggering.

 

I’m flabbergasted that he’s now claiming the “alt-left” is a thing, and a very harmful one at that. Strange that this alt-left didn’t exist until a tweet today, as far as I know, while the alt-right was well established and documented from well prior to Trump’s being elected.

 

I made some very dire and horrible predictions when Trump was being elected. They aren’t exactly mirror image accurate, but there are some horrifying parallels being drawn. Communities are being turned against each other down political, socioeconomic, and racial lines, while Trump taunts a very irresponsible up and coming nuclear war machine in North Korea. The upward distribution of wealth out of middle and lower class communities continues to suck harder every day, causing stock market indicators to soar into the green… A false indication of prosperity while everything stagnates.

 

Where I work, most of the staff are long time veterans. They’ve seen a lot happen around them… Miami burning in the 80s, the Gulf wars in the 90s, Hurricane Andrew, face-eating zombies in Miami, you name it…

 

Nobody could recall ever seeing this same universal reaction of disgust at anyone or anything.

 

That’s a new, horrible accomplishment.

 

*Though the scripts are electronic nowadays and only usually exist within the teleprompter or an iPad, they are still arranged as “pages”. It works, that’s all I know….

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