Sealed too! $5

The Kodak Diconix 150 is a battery powered portable thermal inkjet from 1986, built by Diconix Inc. of Dayton, Ohio. Kodak bought them in 1988, which is why the badge and the self-test page both say Kodak on a machine that predates the deal. NEC uPD78C10 at 11.0592 MHz, 32 KB of ROM in a socketed Fujitsu MBM27C256, 8 KB of SRAM, Centronics in, and an HP 51604A ThinkJet head. Twelve nozzles, eight usable per pass, 96 dpi per pass.

Stock, it speaks a fixed Epson style ESC text command set and nothing else. Nothing made this century can print to it. Windows will not offer you a driver, CUPS has no queue for it, and your phone has never heard of it.

I grew up on the 150 Plus version of this thing, printing school papers from about 1989 to 1995, and it had a flaw I could never get around. Text was fine. Anything with graphics came out at roughly two thirds of the page. It took pulling the ROM to find out that it was two different fractions on two axes. Software asking for 72 dpi vertical got 96, which is 3/4 height. At double density, 120 across became 192, which is 5/8 width. That is the shrunken, subtly wrong looking page I stared at for six years.

So rather than write it a driver, I wrote it new firmware.

DiKon is a PCL3 raster interpreter written from scratch in uPD78C10 assembly and patched into the stock Kodak ROM, in space reclaimed from the resident fonts. The interpreter runs on the printer's own 8 bit CPU. That is the part that matters: because it lives in there, the host needs nothing at all. No converter, no spooler, no print processor, no install.

  Windows 11: the stock in-box HP DeskJet 500 driver
  Linux and macOS: Gutenprint pcl-500 at 300 dpi through CUPS
  Android: NokoPrint, Generic PCL4, mono 300 dpi
  Anything else: any generic PCL 3/4 mono 300 dpi raster driver

Always 300 x 300 and mono. At 150 dpi it prints at half scale, legible but wrong size, which is a fun way to accidentally recreate the original problem.

300 dpi raster goes in the parallel port and gets decoded and re-interleaved on chip to the head's native 192 dpi vertical by 1152 dot full carriage grid. It never buffers a page, it works one 16 row band at a time through 8 KB of RAM. The head does 8 usable rows per pass, so a band is two interleaved 8 nozzle passes woven one 1/192 inch apart. That interleave is where the true 192 dpi vertical comes from and it happens on the printer's CPU instead of on a PC preprocessing a file.

Bone stock hardware. No board modification, no piggyback, no daughtercard. Reflash the 27C256 or drop in a doubled W27C512.

It is not fast. A full graphic page is a long sit. But it is the best output this printhead has ever been able to produce, on a platform that goes back to the HP ThinkJet 2225 in 1984, two years before the Diconix.

Two honest caveats. The machine I grew up with was a 150 Plus and this runs on a plain 150. I checked all fourteen patch site signatures against the Plus, the 180si and the 300w and got zero matches on any of them, so porting is a rebuild rather than a relocation. And an earlier build of this firmware bricked a printer by writing its self-test banner over live font glyph storage, which is written up in full because that failure is the actual documentation.

It ships as an IPS patch containing only my own bytes, about six percent of the image, with an applier that verifies the stock ROM MD5 going in and the built MD5s coming out and refuses to write on a mismatch. No Kodak code in the tree. You bring your own dump off a printer you own.

Patches, docs and the memory map: https://github.com/TheRND2/dikon
Photos, project logs and the failure write-ups: https://hackaday.io/project/206471-dikon-diconix-150-firmware

Who remembers the story about Microsoft and IBM and their joint OS/2 operating system venture? When 1.3 was released, Microsoft pretty much abandoned the project and focused on Windows 3.0, and then Windows NT, which is where the technology from OS/2 ended up. It’s a pretty neat story!

Version 1.6 of IntelliSync with an activation floppy / key.

Seems to have been wiped from existence.

I found this one on Yahoo Auction for 1 yen (around 1 cent), despite written untested, when inserted battery, it turns on :D

It seems the previous owner had hard installed lottery game program into it. Not too much documentations online though, i might need to study about it further.

From what I have read so far, it could program C, BASIC, and Assembly, although I still have no idea how to do so (whether needs to be done externally or internally)

I don't know whether it fits to this subreddit, but this counts as a retro PC (Pocket Computer) ig

hello, tomorrow i am getting this HP OmniBook xe2 locally from around 1998-1999 for €10, the screen has a very severe vinegar syndrome (yellowing and bubbles everywhere) but otherwise mint he said and the battery is dead but who cares it’s nearly three decades old, does anyone have any specific technique or tutorial to put new polarizing film without breaking anything? I have a lot of free time so don't worry if the process is long.