eTokenCard/M4.20
3B
F2
18
00
??
C1
0A
31
FE
55
C8
06
??
mask: FFFFFFFF00FFFFFFFFFFFFFF00
6
Total reports
100%
Success rate
2012
First report
2021-03-31
Last report
ATR Analysis
ISO 7816-3 · local
Full analysis on smartcard-atr.apdu.fr ↗
Convention
direct
Protocol
T=1
Baud rate (TA1)
Fi=372, Di=12, fmax=4MHz, 31.00 cycles/ETU
Guard time (TC1)
0 etu
IFSC (TA3, T=1)
254 bytes
Waiting times (TB3, T=1)
CWI=5 (CWT=43 etu), BWI=5 (BWT≈11,427,840 etu)
Historical bytes
C806
Proprietary / unstructured
TCK checksum
✗ invalid
00
| # | Byte | Name | Description |
|---|---|---|---|
| 0 | 3B | TS | Direct convention (TS = 3B) |
| 1 | F2 | T0 | Format byte: 2 historical bytes, Y1=0b1111 (TA1=present, TB1=present, TC1=present, TD1=present) |
| 2 | 18 | TA1 | TA1: Fi=372, Di=12 → 31 cycles/ETU at 5MHz |
| 3 | 00 | TB1 | TB1: deprecated Vpp programming voltage parameter |
| 4 | ?? | TC1 | TC1: extra guard time = 0 etu masked |
| 5 | C1 | TD1 | TD1: T=1 protocol indicator, Y2=0b1100 (TA2=absent, TB2=absent, TC2=present, TD2=present) |
| 6 | 0A | TC2 | TC2: work waiting time for T=0, Wi=10 |
| 7 | 31 | TD2 | TD2: T=1 protocol indicator, Y3=0b0011 (TA3=present, TB3=present, TC3=absent, TD3=absent) |
| 8 | FE | TA3 | TA3: IFSC=254 (max information field size for card) |
| 9 | 55 | TB3 | TB3: CWI=5 (CWT=43 etu), BWI=5 (BWT≈11,427,840 etu) |
| 10 | C8 | T1 | Historical byte 1 |
| 11 | 06 | T2 | Historical byte 2 |
| 12 | ?? | TCK | Check byte: XOR(T0…TCK) = 75 → ✗ INVALID masked |
⚠ TCK check failed — ATR may be corrupted or masked
2 bytes are shown as ?? because the ATRMask at those positions is 00 —
these bits are variable across card instances and were not recorded. The analysis above is based on the known bytes only.
Use smartcard-atr.apdu.fr with your card's real ATR for a complete decode.