re-recording original cards

Does anyone know how to re-record a clipped (original) card? Could we fake out the reader by simply adjusting the contact that senses a clipped card closed or does it rely on a timed (in particular sequence) signal from that contact?


I re-recorded several cards for a 67/97 standard pack by grounding the write protect switch line. It would seem that the logic is it is looking at the order in which the motor switch and the write protect make, and if it detects the write protect switch first it assumes the card is writeable. This signal is on pin 3 of the CRC.

For a 41 the reader manual says you can override the write protect by setting flag 14.


Maybe you want to read this article on this very site in order to override the write protection -- without the need of opening the calculator and fiddling around with tiny contacts.


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