Great writeup! just here to explain that someone has actually commercialized this project. It is called Printx by evebot. It also comes with a mouse sensor to compensate for movement and a optional gantry for A4 printing. I found this project while tearing down the product I received form the kickstarter. Originally, they were even going to allow people to use it to color 3d prints but that seems to have been locked out by the fact that they will not release the developer sdk.

As Andrew H pointed out; It's most likely a Maxim 1-wire chip, and besides the information he mentioned that's likely to be on it there is a strong possibility it also contains some type of code identifying it as 'genuine'. In fact this code is more than likely the most important function of this chip, at least in my experience (HP among others use these on everything from printer cartridges to laptop batteries as well as the chargers for them).

Thanks for sharing this intriguing project! what patents num about hp 803?

Genius, love your work, and your way to present it. thx for sharing.

Hi,you really did a greate job!And I have a question,How can i burn the code to the pcb with esp32 module?

amazing, how to load grbl firmware on hp pcb

how to reset the hp123 catridge ink level. any idea or hack

can you please add pinout for hp21 cartridge. thank you.

This is amazing!

100€ https://www.indiegogo.com/projects/princube-the-world-s-smallest-mobile-color-printer#/

Bam, another year gone by... Previously on spritesmodes: http://spritesmods.com/?art=inker

Hi sir, firstly thanks for sharing your project. i have been working on a similar project but on a 3d level for my IOT term project. I would like to know which part of your code sends data signals to the cartridge and it will be so much helpful for my if you could give a code regarding generating waveforms from nozdata to sending the data to the ink Cartridge. Thank you

I connected the board to the cartridge by pre-tinning the cartridge pads and with the use of paste flux soldering short (6 mm) 0.3mm solid copper wires to the pads. Then I placed the PCB on top making sure that each wire is in the correct hole. With a clearance of ca. 2mm so that hothing shorts out I then soldered the wires to the PCB. You have to be quick so that they don't desolder from the cartridge. I only got the cartridge to print some random stripes in random colors using the stripped-down "hello" firmware and a color cartridge. What is the recommended procedure for tuning the timings?

How do you connect cartridge contact pins to your PCB?

Thanks for sharing this intriguing project! I'll try to build one of those. Some ideas I had is the addition of a linear ccd sensor such as the tcd1304 or tsl1401 to build something like a pocket copier for ....ehm...whatever. Another nice project would be the addition of an encoder wheel or something similar to print things to scale along the x axis. Really looking forward to building this thing. I've never worked with esp-idf though. Any plans of converting the code to the arduino envronment? Eventually someone will do it anyway :)

m!: That's the joke. The Mona Lisa is indeed painted by DaVinci, but the warped way it's drawn by the cartridge reminds me more of Picasso's abstract paintings.

Great Stuff !! Small addendum: Mona-Lisa was painted by Leonardo DaVinci, of course. Not Picasso.

the ID pin is probably a Maxim 1-wire device or something similar (I2C?) used to identify the cartridge type (color / black) and read/write capacity information, at a guess?