->  TW> Becasue the Printer will NOT work without the proper chip in the
->  TW> Cartridge.

-> if they can use a generic chip (like a rom or a microcontroller)
-> then the tooling cost shouodn't be too high,

 I suspect that HP and the others putting chips in their Ink Cartridges
are smarter then to use a chip that one can easily buy.
It of course cound be Reverse engineered but that is an additional cost
added to the tool up for the chip itself.
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