ID-20 and arduino problems

anyone knows or has a code about ID-20 and arduino ? I am designing an authentication system and when the ID-card is validated I want to turn on a led, after that with the same ID-card I want to turn off the led.

I need to read 4 o more ID-cards with the same configurations.

thanks for your comments.

anyone knows or has a code about ID-20 and arduino ?

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