| 摘要 |
<p>The credit card has two sections of electronic memory (a,b). Each section comprises a number of memory points which may take one of two states. The first is an initial state in which the device is made, and the second is a stable state into which the point may be changed. Once changed into the stable state the point is unchangeable. The first memory (a) comprises the greater number of points, and is used for storing an identification number in binary coded form. The second smaller memory (b) also stores a binary coded number, this being the number of stabilised points used in the first encoded number. Thus the card may be checked to guard against fraudulent alteration, since the second binary number must equal the number of one digit in the main code number.</p> |
