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- Опубликовано: 14 июл 2014
- Teardown Tuesday.
Dave tears down a cash register found in the dumpster.
Does it have any useful parts to salvage?
German brand Quorion QMP 3282
And a look inside a thermal print head.
Datasheets:
www.powertipusa.com/pdf/pg1286...
www.altera.com/literature/ds/m...
www.paradigmtools.com/docs/R88...
www.st.com/web/catalog/sense_p...
www.st.com/web/catalog/sense_p...
www.atmel.com/images/doc0313.pdf
www.onsemi.com/pub_link/Collat...
Thermal print head driver chip: www.dropbox.com/s/bdtmfr2qdsd...
Forum: www.eevblog.com/forum/blog/eev...
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I would love to see a photo of Dave inside the dumpster with just his knuckles over the top edge and the very top of his head/eyes looking out. Too funny. Like, "Kilroy was here".
Would make a great thumbnail!
EEVblog that it would
lets try to make one :)
I've heard that most places don't actually keep any money in their cash registers after they shut down for the day, so the fact that the register wasn't secure probably wasn't actually a problem.
It would have been nice to see the power up sequence, as you described it was quite interesting. Also the software on those devices is at-least as important as the hardware. It's nice to see how displays are used ,how bright, character set etc, and it's nice to hear how piezo sounders are used. "Don't turn it on take it apart" only works when you reassemble the device and power it up afterwards :-). A tear down on dead device is only so interesting, if it's broken of course there no choice. Thanks for posting.
Dave, your comments about bodges on this German product are much more measured than your screams when you see bodges on Asian stuff. The PS is looks really good though.
I love the Tek USB stick beside the scope at the back!
Dave, I would be interested in a episode dedicated to "the art of the bodge." Like what exactly were the symptoms before the mod, how easy is to replicate the failure, why the problem wasn't identified before production, the costs involved, the terror, finger pointing and other drama behind the scenes when you suddenly discover you just 10,000 units that don't work, etc.
Every time I see a bodge on a board, I can't help but think "Man, somebody had a BAD day!"
More like a bad week or month. These things often aren't detected and a solution found in a day. Then yes, all the finger pointing, the endless meeting to determine the best course of action etc. Then some poor bastard has to sign off on the mod again. That's real world engineering.
EEVblog
Are SMD bodges like that common? I've never seen that before.
watch the EEVblog #10, Dave tells a story when a bad rubber band cost one million dollars to a company.
excavatoree I spent a good part of last week soldering on 0603 resistors vertically on other smd component legs. Then run a little wire from the end that's sticking up for a discrete and fairly neat bodged pull up.
I like the idea of reverse-engineering the display interface :-)
Hey Dave I think this would make a nice video. Perhaps with a fundamentals Friday about logic analyzers and different protocols in general.
If you're the same opinion leave a comment or a thumbs up to make Dave aware of.
I'll see what I can do.
Hi Dave! Long time viewer, first time commenter, I have used many different cash registers:
1. yes, they all have some dingy tab to open the drawer, but only if it is unlocked (it only overrides the solenoid)
2. The key you found is for changing the mode, not locking the drawer. The modes are normally: Program, normal, void, off. one key (user) will let you turn it on and off, the other (admin) will let you program it and void sales. This is why it is not a really secure key.
3. programming these things is only slightly better then a root canal;
Put in PGM mode
enter 1001 press PLU then 1100 press PLU then AM/TD
Enter 1011 Press PLU then turn gey to Void and press AM/TD
and so on and so on. it is horrible.
Thanks for the tear downs! I enjoy ever single one of your videos. First the scanner and now the register, complete convenience store package.
Toilet paper dispenser with a cutter mechanism.
Electrical tape slicer?
Exactly what I thought of too! LOL!
yes...with kids...we go through a roll of TP a day because they use WAY too much..
dude! my exact thought!!
Try teaching them to fold it intead of just scrunching it up into a ball. Helped lower my usage greatly once someone told me to do it like that ( That was at about age 6)
That cutter assembly could make quite a nice tape dispenser for PVC or Kapton, for those times when you need three hands.
or any big teeth sawblade
wayback old cash registers used to be a way of getting a cheap uc training system, when the very first casio electronic registers (more basic than that one) started getting dumped (mid 80's ish) someone had produced a prom with a monitor program on it which you sent off for to an address in an electronics magazine advert - pre youtube hack!
you had to assemble your machine code by hand and type it in through the keypad byte by byte, the VFD was your visual display and iirc there was no long term storage for your work. We had one at school - it worked but you only had about enough time to flash a led before it had to get switched off again at the end of a lesson. by that time a lot of kids had BBC and sinclair micros at home anyway which made it seem pretty unimpressive.
sorry for waffling up an old vid, just thought the people who've grown up on arduinos etc might be interested
the circuit board on that looked surprisingly clean given it had been used in a cafe
While I am a rank beginner with electronics despite years of messing around these are fascinating. Dave is the man!
I don't really get what is going on in your videos, yet I still watch them. Wonderful.
The EEVBlog, Teaching people how to rob cash registers since 2014.
yep, I might check for that the next time I do work on a credit card machine (the place I work had the PoS separate from the credit card machines)
I like to cater to all audiences.
EEVblog
And that's why I'm a subscriber. Thanks Dave.
The shop i work in had a release button on the till but it had to be covered as it was part of a compliance audit we usually just taped a cd cover over it, though most modern ones will have the power loss release built into the keyhole, centred unlocked, turn right to lock and left to release the drawer
Thank you so much! I finally found out how to separate the top part from the bottom drawer! Excellent! So, I can now use only the drawer while I take the top part to fix.
This is really cool. As I work for military defense, all this "afterthought circuitry" is a real thing and hasn't gone anywhere! Sometimes we have to get a product out, and scotch tape and lead solder is the only way!
Scanner = bar code scanner?
Yes, indeed.
Fantastic find, Dave. That vacuum number display is excellent! I always enjoy your videos.
Only Dave can make a cash register fun and interesting! Thank you :)
A non-contact toilet paper dispenser.
Very nice Dave!
I really love your teardowns, which i myself already did as a kid.
BTW, i think the cutter mechanism doesn't cut the paper completely, in the middle there would be a little spot left uncut. Then you would have a chain of receipts instead of a bunch of individual sheets of paper.
Keep up your style!
Auto Toilet paper cutter!!!
Make it Arduino controlled and it'll hit the front page of Hack-A-Day!
EEVblog The problem there would be, that you need something to hold the paper, otherwise it would fall down as soon as cut. OR it will only cut the paper the instant you pull it, basically making the pulling even easier... Well... Somehow interesting Idea :D
Maximilian Mustermann It would not fall. If you look carefully at the cutter, at the top of the "V" shape there is a notch where paper is not cut. It stops the receipt falling from the machine :)
chris746568462 oh, nice :D but would that be enough to hold back multiple sheets of toilet paper?^^
Maximilian Mustermann For "Heavy" Users, probably not lol!
Really cool what you find inside of old devices.
I'll gladly give this teardown a Thumbs Up & a Kerchinng!!! for added value. :)
Very interesting ! In the shop were i am working we use small battery-operated thermal printers to print out price stickers and such. I believe that on the inside they should be looking like the one in this video, But they definitely have less DPI.
moar ferrites! XD
also the cutoff mechanism is a must for a microcontrolled toilet paper dispenser ;)
Probably too flimsy to be effective on toilet paper. Well, unless you buy the cheap stiffer crap.
great video, interesting to see inside this unit!
Don't know why I subscribed after seeing this vid, maybe his passion for these thing we take for granted, I'm not sure but it entertained me, and I think I learned some thing?
Cool teardown, Dave! Tanx for this one. I like the VF Display best, as it is a very big one...;)
More useable parts than a inkjet printer!
for those wondering about the mode switch, the x is for a running PLU report (usually an hourly report) that does not clear the stored PLU information. The Z mode prints out a report of every item from the last time a Z was done, and it clears out the information. Not sure about the other modes, but X and Z are pretty standard for PLU tracking systems
Don't forget the solenoid! You can salvage that puppy too. I tore apart an old tape based answering machine and found 2 solenoids for salvage inside of that guy not to mention some of other useful parts.
Very interesting as always ! Keep up the great work!
Your building throws out a LOT of electronic devices.
OMG the amount of finger crud on that keypad.
For a bodge though, that is a really clean, well engineered one. They actually bothered to put a connector and everything.
casio made the best registers. they were a pain in the ass to program, but they had so much functionality for PLU tracking. good times
When I worked at my dad's restaurants, all the cash registers had the option to open the drawer manually. The mechanism is always stick your finger in the back, on the bottom of it. Normally the register is against the wall, and is heavy due to the weight of coins in it, so it is not easy to raise it and open it, but when you need to, you can. When will you need to?, easy: when you have no electricity, and a customer comes in, and of course you have handy the manual paper invoices.
The cash register is not a safe box replacement.
I have used thermal printers before for some fun wankey little projects ... twitter reader, joke receipts, printing out small things ... i stuck a little ATMEGA32u4 breakout in one and put it in a nice box ... unfortunately broke when my power supply failed!
im most excited by that VFT ... i absolutely LOVE VFT displays but there soooo expensive!
Keep a eye on the noritake-itron sample site. They have very reasonable prices and often offer substantial discounts (50% off at the moment). Their evaluation kits are first class with excellent documentation and pre-made libraries.
Thanks allot!
some dvd players have VTF displays
I'm gonna go join the eevblog forum because I actually want to be part of your community. I have so many questions, and I don't want to keep bothering you.
I want to thank you Dave for explaining the low-impedance ground return to avoid ground-bounce.. I have an FPGA project that bounces like a space-hopper when the data lines are pulsed and will look into this kind of work-around! (I think the chinese company that built the gate array board under spec'ed the bank-caps, but will try this as a first port of call) - Nice one! & Regards from the UK :D
Love it. Will soon order a second one.
So many bodges on this device. More than any other you've shown. Several near the battery as well.
the key switch on the side is for doing daily and weekly totals in X and Z modes.
That paper cutter ? Perfect for a fully automatic toilet paper dispenser! Just wave your hand in front, TP rolls out, gets cut and you don't have to do all that hard work manually!
gotta love teardown tuesdays!! i would love to see the reverse engineering of that VFD, i have two of them from VCRs and i have been meaning to use them
Automatic toilet paper cutter?
Also I love your videos. They have helped inspire me to pursue a career in engineering.
You can use the thermal printer to make a mini teletype computer running a Tiny BASIC! That would be an awesome project!
Might be interesting (and karmically appropriate) project to combine this with the laser barcode scanner and turn it into a shopping list generator. Wave a product you've used up at the scanner and it stores it with a microcontroller and then with touch of a button it could print up a shopping list of what you need to re-stock.
For about 10 years i've used an ex McDonald's cash drawer in my bedroom to store things like spare keys, cigarettes, a bit of cash, screws and other random small things. I drive the solenoid with 12v, with a button hidden nearby.
It doesn't have a finger release but the lock is so easy to pick that you could probably do it with one bobby pin.
I guess cash registers don't really need to be very secure because if a staff member wants to steal money they can always just open it. And if someone robs the place they could often just take the whole drawer or have a staff member open it.
I have an Idea for the paper cutter ... I think it would make a nice toilet paper cutter for those mornings when you just don't have the energy to tear off a piece of TP
The thermal printer can be used as a roll-mode oscillograph. Saving low frequency wave or data on paper.
i think a Facebook/twitter printer based on this printer and a raspberrypi would be awesome! Something that would print out every post of a specific hashtag :)
Would really, really love to see that! :)
This video caught my eye, (though I do watch 90% of eevb anyway) because I have a love for cash registers, have always wanted to have one, only thing stopping me is I have zero practical use for one and my bedroo.... "lab" is already cluttered enough XD
Dave, check that VFD for severe burn-in, if it has been running static, which they usually do, re-purposing it will be a bit sad :/ - but try to document reverse-engineering the interface!
I would use the thermal printer for shopping lists or similar. Used one at work for that, that we ripped out of an old cable tester.
Personally I mostly salvage motors from my tears downs even though I rarely use them.
Motors are just such nice things. Hard to toss out.
you could use the cut off mech for bigger self stick labels for your boxes on your shelf's.
I would really like to see what you make from all of these dumpster dive component saves ! Would be great to see you build something free and useful out of all these saved and re-purposed items. :-)
Having pulled apart many cash registers, I think your lucky this wasn't an ex Pub machine. Nothing like the stench of 10 years of stale beer and cigarette smoke.
If I had all the equipment you have, I would probably reverse engineer the hell out of it, the thermal printer, the vacuum display... hope to see something like that. cheers :)
Make a packing tape dispenser with the cutter! :)
Turn the thermal printer head into a FLIR persistence of vision display? Delightfully impractical :-)
That thing is ate up with bodges. At 13:55 you can see a through-hole inductor or something soldered across the tops of some surface mount parts near that backup battery.
and what it looks like a bodged cap right next to it..
That's interesting; I didn't know that those little LCDs out of stuff like that could be useful again for other projects. How would you go about hooking one of those up to a computer and interfacing with it?
That tray's not locked then. You've just bypassed the button to open it. When locked, there's a metal bar preventing it from sliding out.
all cash registers have that little button at the bottom
JydenStudsgaard so does mine, i have one in my claw machine in my oom
The drawer reminds me of the ones from the Samsung ER-6500's, same layout and design.
Just a short idea for the cutter thing. Toilet paper cutter, after length X based on a sensor.
I had a couple of TEC registers i was given. Same model person thought maybe i could swap out things and make one wok, and do something with. Even though same model interfaces, etc were totally off. I scraped them. Printers in mine were like a dot matrix setup of sorts. A row of solenoids that tripped these arms with i want to say the various characters on the end that ran by an ink ribbon and put the marks on the paper.
Hate digital cash registers love antique cash registers enjoy collecting them!
Any place I've ever worked at you can open a regester with a pen or your finger on the underside of the drawer
I've seen it on a lot of cash registers/POS systems too. I guess people always lose the keys, so they need a backup.
what are the ferrites around the wires for?
The key lock was actually not locked, the drawer just will stay closed unless you finish a transaction or press the manual release. If the drawer was locked, neither would have worked.
Idea for the paper cutting mechanisem: Full auto toilet paper cutter.
Hi everyone,
I got a defect Philips PM3240 scope. The screen seem to light up but I get no trace. Any idea where to begin my troubleshooting? :)
Is channel A turned on (to left butten I guess)? Tried to play with Position and AMPL in the left section thile it's set to 0 on the bottom switches? Trigger (right) on AUTO and channel A? Are you sure the screen is actually on? The (orange?) grid-backlight controlled by illum is unrelated to the actual CRT screen.
Thermal printers are a good output device for projects using a raspberry pi or arduino. I wouldn't bother with one unless it had an rs-232 interface though.
I work in retail, Every cash register has that safety feature so you cant lock yourself out of your own till
Nice piece :D thumb up!!!
On the under voltage bodge at 8:06, is there a chip resistor between the left hand and middle lead of the Motorola device? Wow. Aside - The 8:06 above becomes a link to the correct spot in the video! That is why this is a repeat to change the time stamp. Very nice RUclips!
Hi Dave! New sub here, I love your channel, it's very interesting to learn more about electrical components within, well, electronics. I've disassembled everything within my household I'm comfortable with doing so as I'm becoming more and more excited and interested with working on the actual hardware within electronics. But quite honestly, I don't understand 95% of what your talking about. I want to learn more, but your stuff is too advanced. I'm curious as to if you'd begin a fun "soldering beginners video/day" for a lack of better words or maybe even turn your second channel into one? Haha, Never know right? Mainly to attract more new viewers like me. I'm sure you've heard of Kip-Kay, I'm not a huge fan of him although I am subbed to him because he makes some very interesting/easy/fun soldering or even "electrical engineering" work (I guess would fit no?) that's simple enough for everyone to do. The fact of the matter is, I can only watch so many of your video's (and that’s out of pure entertainment). So like me there must be many many others that are in the same situation as me. I like you (underline) and your video's, but at some point I'll need to follow someone else to actually start learning how to get to the point where you are now. Hope you will give this some honest consideration, and out of gratitude I'de be personally taking time to advertise this channel out of excitement for anyone new to soldering/electrical engineering to learn from. I say soldering though in my mind I'm thinking of creating my own circuit boards for use rather than fixing or buying. Just my lack of knowledge at this point. Hope you can change that! Thanks for the vlog and reading, hope to hear from ya! Thx
What is the rationale in (14:40) raising the power resistors & off the board?
Use the cutting unit to make a packaging tape dispenser. Maybe you could have Sagan help you
Was that a surface mount resistor soldered between the leads on the reset chip?
I am from Germany and I am a little shocked about the quality of that "German Engineering". Dave showed that Prema multimeter made in Germany a few videos ago, which also was full of bodges. A shame! Is it all only marketing?
do you dig through dumpster or what? How do you find all of this?
I cannot understand 95% of what he is saying...yet I continue to watch these videos lol
On the under voltage bodge at 8:40, is there a chip resistor between the left hand and middle lead of the Motorola device? Wow.
Amazing how you can score from what you expect to be cheap stuff.
You could use the printer for a bitcoin qr code vending machine. Prints out qr codes so people can scan them in with their devices.
That seems like a huge amount of processing for what I thought would be a fairly simple job. I would've expected a micro, some memory, and a handful of IO expanders. Why so much stuff?
Probably more for the ease of software development on the PC platform. The software wouldn't be easy though, tons of user configurability required.
First time i have heard a Nerd with an Australian accent lol.
toilet paper cutter :D
Dave can you do a video on how to figure out the display boards. Thanks
Was the printer return ground through the logic board still connected or had it been cut?
Why are the parts offset on the power supply? I thought wobbly parts are bad?
In a fixed product like this it's fine.
Can termopriner can be reverce engeneered? Will be nice to have it!
Use the printer for Freq counter output.
EEVblog one project idea for the thermal printer since you tweet so often. Set it to print out tweets mentioning you, or direct messages etc.
Hehe I should do some tear down videos of some stuff I have here.
There is something from goodwill that I got that does not work and want to ask if any one can figure out what is wrong.
Although I am thinking it is the Lazer as it skips pretty badly.
It is a 300 disc changer,
There is also an old coffee pot that I should tear into on camera as I wanted to try to fix it if I could.
As it was a fairly pricey coffee pot.
I just never have done anything with the coffee pot as it has freaking security bit screws holding it together. :|
1:12 That's what I call teardown.