Using the character waiting time the initial value
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| Table 6.38 |
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| default value of 32 bytes also applies to the card (IFSC = information field size for the card), but this can be modified by a parameter in the ATR.12In practice, the size of the I field for |
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The single-byte longitudinal redundancy checksum is computed using XOR concatenation of all previous bytes in the block. This computation can be executed very quickly, and its implementation is not code-intensive. It is usually performed on the fly during data transmission or reception. It is a standard part of practically all T = 1 implementations. Using the CRC procedure to generate an error detection code yields a much greater proba-bility of error detection than the relatively primitive XOR checksum. However, this procedure
12 The TAi (i > 2) data element in the ATR
13 See also Section 4.5.2, ‘CRC checksums’
| 6.4 | 413 |
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The primary purpose of the send sequence counter is to support requests for resending blocks received with errors, since individual data blocks can be unambiguously addressed via N(S).
6.4.3.3 Waiting times
CW T = (2CW I+ 11) work etu
The default value for the CWI is 13, which yields the following value for CWT:
