fotofreek said:
We don't know if the prism is responsible for telling the chip that the cart is low or out of ink or if the chip keeps some sort of count on ink used. If the prism signals the printer which in turn sets the chip on the cart to show low or empty then the solution to the whole chipped cart issue is to visually check ink levels and refill before the ink gets down to the level where it exposes the prism. Anyone out there who has just bought a chipped cart Canon and intends to refill? Try refilling when any cart gets down to less then half full and see if you ever get the ink low or out signal. You won't if the chip relies on the prism to reset to a "dead soldier."
I can confirm that the prism is definitely involved somewhere in the process because of the following observed behaviour.
1. The prism is still part of the design (and yet they've changed the cartridge design itself) so it must have a function
2. The cartridge will trigger on an empty cartridge (if it's emptied manually)
3. The printer will not allow you to continue to print if the cartridge is actually empty so if you refill, it then changes its mind and displays the 3 warnings re: warranty, etc.. The only way it could know you've refilled is via a sensor which the prism is and I refer back to point #1.
Of course I could actually be wrong and they've left it in as a false flag but I'd lay a $100 bet that Canon aren't that stupid.. it's there for a reason.
As to whether you can disable it.. I haven't tried yet but it's on the cards.. That wouldn't stop the chip calculating the nozzle firings and declaring the cartridge "empty" anyway as I've found with my CIS kit (ie: carts all full but being declared empty after a certain amount of work).
What is completely unknown is how the printer interprets different situations and reacts.. At present it's apparent that Canon have done something that uses the Prism and chip in a way to make refilling very difficult if not impossible over the long term but as Osage pointed out recently it all comes down to applying inputs (scenarios) and seeing how the printers react to understand how to circumnavigate their little tricks.