ATR statistics: TC3

Ludovic Rousseau

2019-03-17 16:37

Article from the series "ATR statistics".

TC3

The ISO 7816-3 specification is not public. So I can't copy/paste part of the text. I will use Wikipedia instead.

For T = 1: type of error detection code used

Bit 1 of the first TC for T=1 indicates the error detection code to be used:

CRC if bit 1 is set to 1;
LRC (default value) if bit 1 is set to 0.

Bits 8 to 2 of the first TC for T=1 are reserved for future use and shall be set to 0.

TC3	#	%
	2017	97.35 %
0x00	55	2.65 %

In my list of ATR the only redundancy code used if LRC. I found no card using CRC.

LRC is the default algorithm. But 55 cards explicitly set it. I have no explanation for that.