ATR Info Gemalto Classic TPC IS | ATR Infos Starcos SPK 2.3

ATR Info Siemens CardOS 4.3B

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ATR: 3b f2 18 00 02 c1 0a 31 fe 58 c8 08 74

From the ATR of the CardOS 4.3b resp. its single bytes (left column) there can be derived the parameters values (right column). The notation 0xhh means Hexadecimals.

From the ATR you learn the values for minimum and maximum frequenz, the conversion and adjustment factors for baudrate, the programming voltage, the used protocol (T=1) and more.

ATR Bytes	Parameter
TS=0x3b (direct)	f(min)=1000kHz (default)
T0=0xf2 (Y(1)=15,K=2)	f(max)=5000kHz
TA(1)=0x18 (FI=1,DI=8)	Fi=372
TB(1)=0x00 (II=0,PI1=0)	Di=12
TC(1)=0x02 (N=2)	N=2
TD(1)=0xc1 (Y(2)=12,T=1)	P=0dV
TC(2)=0x0a (EDC=0)	I=25mA
TD(2)=0x31 (Y(3)=3,T=1)	X=Not supported (default)
TA(3)=0xfe (IFSC=254)	U=A only (default)
TB(3)=0x58 (BWI=5,CWI=8)	IFSC=254
T1=0xc8	BWI=5
T2=0x08	CWI=8
TCK=0x74	EDC=LRC
	T(supp)=1

	IFSC (Maximum information field size for cards): maximum length of blocks the card can receive
	BWI (Block waiting time integer): is used for computing the "block waiting time" (BWT). The maximum delay between rising (front) edge of the last character in a block to the rising (front) edge of the next block.
	CWI (Character waiting time integer): is used for computing the "character waiting time" (CWT). The maximum delay between the rising (front) edges of to consecutive characters within a block.
	EDC: Error detection code: indicates used kind of Error Detection (LRC, CRC).

Meaning of the Parameter

As seen above, the single bytes of the ATR indicate certain values.

f(min): minimum frequency for communication with the card
f(max): maximum frequency, for communication with the card
Fi: Clock rate conversion factor.
Di: Baude rate adjustment factor.
N: Extra guardtime
P: programming voltage
I: programming power
X: Clock stop indicator
U: Class indicator for operating condition. class A = 5V, class B = 3V
IFSC: Maximum information field size for cards; maximum length of blocks, the card can receive
BWI: Block waiting time integer. The maximum delay between rising (front) edge of the last character in a block to the rising (front) edge of the next block.
CWI: Character waiting time integer. The maximum delay between the rising (front) edges of to consecutive characters within a block.EDC: Error detection code. Gibt die Art der Error Detection (LRC, CRC) an.T: Protokoll Typ.

Conclusion

The performance results of a card reader depends strongly on the used smart card. To compute the etu (elementary time unit), the time length for transmittance of one bit, you need the frequency and the conversion and the adjustment factor. The formula is

1 etu = (F/D) * (1/f)

F = Clock rate conversion factor
D= Baud rate adjustment factor
f = Frequency (Hz)

Concretely the Siemens CardOS V4.3B card results in an etu about ap.6 ms (Fi = 372, Di = 12, f = 5 MHz). For the user more interesting is the baudrate of the communication with the card. You can compute it with:

Baudrate = (f/F) * D

The CardOS 4.3b has a maximum baudrate of 161290. This value is accepted by the card. Crucial is the frequency of the card reader - resulting in other baudrates. Due to this facts it is possible, that a card reader can communicate very fast with one card, while another card seems to be extremely slow. You can see this perception in your Reader Test.

ATR Info Gemalto Classic TPC IS The Gemalto Classic TPC IS (GemSafeXpresso) contains two ATR. With first reset the ATR 1 is sent to the reader, if the reader cannot work with the parameter, the second reset..