Teardown Tuesday - An ink cartridge?
Yep. Why not. It has a few cool bits in it.I picked this up from pile of discarded stuff at the old office. Everyone was getting ready to move out of the old building as Insurance.com and the CoMa agency were packing up shop.I picked it up because I noticed something peculiar.This is pretty much normal. But when I flipped it over:A chip!A bit of prying on the tab adjacent to the chip produced this:And there's nothing on the back:Before I tear into this... the rest of the device!On the bottom I had already ripped out the pad that was covering the hole. Even after sitting out (on the hearth En reminds me) I pried out a ball plugging up the smaller opening. No doubt this is the fill hole. The ink is injected then the hole is plugged with the plastic ball. Presumably the plug up the large feed hole while it's being filled.Of course as the ink is injected into the cartridge, the air that's being displaced needs to go somewhere as it's filling:There you have it! The bit of labyrinth is to catch any overflow that might happen during either filling or other rough handling after the fact -- it allows air to flow freely while trapping any ink that might spill out.Now -- back to the chip.The markings are L56 W127 9M. This turns out to be a ROHM EEPROM. Specifically a 2Kbit (1/2 KB) serial EEPROM that is used for nothing except "security." Since this is an EEPROM this can be programmed on the fly by the postage printer as well. Every impression can count down the number that's "left in the cartridge." I put it in quotes since there seems to be plenty of ink left. Such a waste.If I had something to hook up to this I could read out the bits one by one and see if I could reverse engineer the coding -- not that it makes a damn bit of difference to me.[smugmug url="http://photos.vec.com/hack/feed.mg?Type=gallery&Data=20106991_SFpQCz&format=rss200" imagecount="100" start="1" num="100" thumbsize="Th" link="lightbox" captions="false" sort="false" window="true" smugmug="true" size="L"]