[HN Gopher] Cat Printer
___________________________________________________________________
Cat Printer
Author : newman314
Score : 208 points
Date : 2022-03-25 16:34 UTC (6 hours ago)
(HTM) web link (github.com)
(TXT) w3m dump (github.com)
| ursaspark wrote:
| looks like this is a variant of the other "portable mini thermal
| printers" available on aliexpresss
| https://www.aliexpress.com/item/1005002247175933.html
|
| possible these are compatible or at least similar enough, many
| similar products re-use modules and microcontrollers.
| Karliss wrote:
| Did anyone else notice that title of word document in the
| second product image is "From spyware with love"?
| jan_Inkepa wrote:
| I bought one of these because it was advertised as usb, but it
| being Bluetooth-with-special-(mobile-only!)app-only meant that I
| returned it. Nice to see someone jailbroke it :)
| ComputerCat wrote:
| This is absolutely adorable!
| pnemonic wrote:
| Lol'd at "Mean Threshold:" and then Grumpy Cat.
| WoodenChair wrote:
| How would one go about reverse-engineering Bluetooth LE? Is it
| looking at packets through WireShark?
| anfractuosity wrote:
| If there is an android app for the device, you can easily log
| the BLE data and load into wireshark
|
| https://www.mybluetoothreviews.com/what-is-bluetooth-hci-sno...
| shows how to capture the packets (you just go to the developer
| settings to turn it on)
| tunaoftheland wrote:
| Not reverse engineering, but I'd used free iOS/macOS apps that
| could inspect the traffic content. I also had access to the
| spec sheet from the manufacturer ("smart" BLE scale) that had
| where in the long payload digits were the weight, body fat, and
| water content, etc. Kinda fun and frustrating at the same time.
| If you truly wanted to punish yourself, you'd be doing this
| while trying to write a React Native app that communicated with
| the scale over BLE. :)
| ctoth wrote:
| Using something like this[0].
|
| [0]: https://greatscottgadgets.com/ubertoothone/
| tyingq wrote:
| Cheap device that can sniff BLE and send it to Wireshark:
|
| https://www.adafruit.com/product/2267 ($20)
|
| Overview on using it as a sniffer:
| https://learn.adafruit.com/introducing-adafruit-ble-bluetoot...
|
| Still a lot of work though, if it's anything like LED signs
| I've reverse engineered. Trying to figure out if it's length
| encoded payloads or delimited payloads, what obscure checksums
| it might use, weird encoding of images, etc. And experimenting
| often hangs the device, or changes it's behavior significantly.
| RBerenguel wrote:
| There's also PPA6 for PeriPage thermal printers, a Python library
| using reverse engineering of the Bluetooth messages intercepted
| to the device:
| https://github.com/eliasweingaertner/peripage-A6-bluetooth
| tombert wrote:
| I wonder, if I wanted to recreate the Gameboy Camera with an
| emulator...has anyone done this with a webcam and a thermal
| printer? How hard was it?
| RL_Quine wrote:
| Yes, emulators support the gameboy printer. In hardware it is
| implemented very close to the way the screen is written.
| tombert wrote:
| That might be fun then; have the emulator write to a thermal
| printer, relive a bit of nostalgia I have for the awful
| printouts of Pokemon characters I used to have (and might
| still have in a box somewhere actually).
| _def wrote:
| Next step: make a DIY gameboy printer that works with a
| real gameboy
| iamjackg wrote:
| Most emulators are able to export a PNG that you could then
| print with something like this project! They don't support
| using a webcam with the ROM for the Game Boy Camera though.
|
| If you buy the real thing, there are lots of projects for
| extracting and printing the pictures though.
|
| This project implements a fake GB Printer that you can then
| access via WiFi to download the prints:
| https://github.com/zenaro147/NeoGB-Printer
|
| This project I wrote a while ago allows you to use a printer
| very similar to the one in this submission as an actual Game
| Boy Printer, connected to an original Game Boy:
| https://github.com/iamjackg/esp32-phomemo-gameboy-printer
| rosstex wrote:
| Well that's the fastest I've purchased anything in a while.
| bitwize wrote:
| The perfect accessory to go with your bear computer:
| https://i.gzn.jp/img/2009/07/13/rilakkuma/rp_001.jpg
| ta8903 wrote:
| bear computer
| gardaani wrote:
| The design is as cute as Nabaztag / Karotz:
| https://en.wikipedia.org/wiki/Nabaztag
| boomboomsubban wrote:
| The design is Rilakkuma, and seems to predate Nabaztag.
| https://en.wikipedia.org/wiki/Rilakkuma
| ellisd wrote:
| I'd love to print to a Cat Printer from an iOS device via
| AirPrint. I see a ton of AirPlay to CUPS projects on Github, but
| I'm not quite sure how CUPS would be configured to simply call
| the Cat Printer python script. Any pointers on how to leverage
| CUPS or should I simply focus on an AirPrint server that directly
| calls Cat Printer?
| bo0tzz wrote:
| I would take a look at https://en.opensuse.org/SDB:Using_Your_O
| wn_Backends_to_Print.... Going off a quick glance at the code
| examples, I think it might be fairly straightforward to hook
| into CUPS. https://github.com/jsmeix/cups-backends also has
| some useful looking tools.
| sho_hn wrote:
| I just bought a Phomemo D30 thermal label printer to label my
| electronics component boxes last week, and I was wondering if I
| can hack things to send it images from my PC instead of the phone
| app it comes with.
|
| I found this repo, but I don't know if that's compatible with the
| D30 (the chassis pictured is of a different printer):
| https://github.com/vivier/phomemo-tools
|
| Someone in Issues asked the same question, but the author wasn't
| able to answer for lack of hardware. I guess I need to try and/or
| contribute!
|
| The "Print master" phone app is uploaded under a different brand
| name (QUIN LLC), and other brands also seem to sell a D30
| printer. I didn't really do the work of finding out where these
| truly come from. Perhaps someone's got a repo up under a
| different name.
|
| I've done 0 comparisons to other models in practice, but FWIW it
| does what I wanted it to do very well. All my stuff is
| obsessively well-labeled now. In fact, I labeled the printer in a
| mad-with-power move ...
| https://eikehein.com/stuff/label_printer.png
| zwass wrote:
| I actually just picked up the exact same printer but hadn't yet
| had time to see what OSS libraries were available yet. I had a
| previous project where I printed photos on a low res thermal
| printer. The images sucked, but people loved it.
| conroydave wrote:
| great now make it print github issues
| afandian wrote:
| https://news.ycombinator.com/item?id=30803589
| vageli wrote:
| I would love to learn more about the reverse engineering process
| for a bluetooth device like this. It's too bad there is no link
| to a blog or additional documentation in the repo.
| szundi wrote:
| You can buy a Nordic Semi usb devkit and their software can
| sniff. Maybe you can have the Android sw run in a virtual
| device and catch api calls
| Karliss wrote:
| The repo states that they reverse engineered the Android app.
| So potentially 0% BLE specific reverse engineering and 100% of
| android Java. In some cases reverse engineering java code,
| which decompiles relatively well, can be easier than trying to
| sniff bluetooth packets, potentially dealing with standard
| bluetooth encryption and guessing what the raw bytes do.
| bilkow wrote:
| You can decompile android apps, which will give mostly the
| original Java Classes / functions with anonymized names (class
| A, function b, etc...). Framework classes and methods usually
| stay pretty much the same.
|
| See for example https://github.com/robertohuertasm/apk-
| decompiler and https://github.com/vaibhavpandeyvpz/apkstudio
| (only used the first one but the seconds looks practical)
| snvzz wrote:
| Open printers of any kind are very welcome.
|
| I dream on an OSHW laser printer, engineered to be cheap, durable
| and easy to repair, with none of the bullshit manufacturers have
| been pushing on people for decades.
| spoonjim wrote:
| I don't know about repair but the $99 Brother laser printer
| doesn't require any malware. You can print wirelessly from
| Windows/Mac/iOS without installing anything
| dylan604 wrote:
| I recently became much less enamored with my $99 Brother.
| There are certain paper types that it has issues pulling from
| the paper tray, but it can use it from the manual feed.
| However, the manual feed will not pull it straight and
| everything comes out at an angle.
| PaulHoule wrote:
| If you get a cheap printer you have to buy expensive paper.
|
| I have the worst time printing in my house because the
| relative humidity level is very high in the summer. In the
| summer when my hair is curling and curling and curling from
| the humidity I have prints curling and trying to come off
| the walls. (In the winter I complain that static
| electricity is making my hair stand up on end.)
|
| You can't save money by buying 20 reams of paper on
| discount from Staples because the paper will soak up water
| and misbehave when you try to use it.
| tln wrote:
| Interesting... what are you printing?
|
| I've had my brother laser for just about 10 years now, it's
| been awesome, regular paper, 80# cardstock and shipping
| labels being no problem from tray or feed.
|
| Envelopes haven't been great.
| dylan604 wrote:
| Labels of various types that have specific places to
| print on the page is the issue for me.
|
| There's a test page that can be printed that shows
| alignment. The docs say to try something if it comes out
| skewed, but if that doesn't work then to take it to a
| certified place blah blah. It's clearly out of warranty,
| so that's a no go.
|
| I recently upgraded capabilities as doing more than could
| honestly be expected of a $99 printer. It has been well
| worth the expense of a higher model printer.
|
| Outside of that, I still love my $99 Brother B&W laser
| with scanner for anything not specialty labels. I look at
| it like not getting upset that a 1980s Yugo doesn't get
| nearly the same lap times as a 2000s model supercar
| lelandfe wrote:
| If you keep an eye out, you can snag one for much cheaper on
| eBay! The one I used back in college was great, and I picked
| it up for around $40.
| newman314 wrote:
| Fun fact: did you know that you can netcat firmware to a
| Brother printer?
|
| It's both cool and terrifying.
| vhold wrote:
| See also: https://github.com/nmap/nmap/issues/2237
| denysvitali wrote:
| Well, you can literally print a firmware on some printers,
| and it will install it. Not sure what's worse
| tombert wrote:
| I find that giant office printers have given me a lot fewer
| headaches than "consumer" printers. I have a fifteen year old
| HP that I bought used on Craigslist for like $100, and it just
| magically worked upon plugging it into my router. I just use
| the generic Postscript driver on Macos.
|
| I don't think that driver is open source, but I suspect that
| you could fairly easily get a generic Postscript printer
| working with CUPS.
| rhplus wrote:
| Did it come with a hard-drive filled with copies of every
| corporate document it had ever printed?
| kingcharles wrote:
| LOL. The amount of shit I've bought off eBay and Craigslist
| that hasn't been wiped is significant. And that's without
| being totally bogus and actually putting any effort into
| data recovery which would surely work on most devices.
|
| Phones were crazy. So. Much. Homemade. Porn.
| tombert wrote:
| I've purchased used laptops that weren't wiped, and found
| fairly elaborate tax documents and other identifiable
| info on there that I could easily have abused.
|
| I'm not a douchebag, so I just wiped the disk and didn't
| do anything with it, but I suspect that there must be an
| entire industry of people buying used computers or hard
| drives on Ebay and stealing data off there.
| ComputerGuru wrote:
| I just want to definitively confirm that such an industry
| exists. For some time, there were people buying used
| phones, recovering sexts, and extorting the sellers
| (whose name, email, phone, and address they now had
| courtesy of eBay).
| nanochad wrote:
| gumby wrote:
| > Phones were crazy. So. Much. Homemade. Porn.
|
| Any of it good?
| vangelis wrote:
| Hopefully they did the right thing and factory reset it.
| tombert wrote:
| You know, I don't know...it might? I never opened it up
| enough to look for a hard drive.
___________________________________________________________________
(page generated 2022-03-25 23:00 UTC)