DS8007A Maxim, DS8007A Datasheet - Page 33

• Manufacturer Part Number: DS8007A
• Description: The DS8007A multiprotocol dual smart card interface is an automotive grade, low-cost, dual smart card reader interface supporting all ISO 7816, EMV™, and GSM11-11 requirements
• Manufacturer: Maxim

The DS8007A supports I/O communication and CLKx
frequency generation compliant to the following stan-
dards: ISO 7816, EMV2000, and GSM11-11. Each of
these standards has an allowable CLKx frequency
range and a defined relationship between CLKx fre-
quency and ETU (baud rate) generation that is support-
ed initially and after negotiation.
For ISO 7816, the relationship between ETU (baud rate)
timing and CLKx frequency is as follows:
The minimum CLKx frequency is fixed at 1MHz. The
default maximum CLKx frequency is 5MHz, however,
the maximum CLKx frequency can be increased
according to the Fi parameter given by the card during
Figure 11. ETU Generation
f
2 x f
CLK
CLK
UCR2x.CKU
0
1
ETU = (F / D) x (1 / f
RSTx
START BIT
______________________________________________________________________________________
Multiprotocol Dual Smart Card Interface
Standard Clock Frequencies
UCR2x.PSC
PRESCALER
PRESCALER
/31: PSC = 0
/32: PSC = 1
/31: PSC = 0
/32: PSC = 1
CLOCK
CLOCK
CLKx
and Baud Rates
GATE
)
CLR
ETU GENERATOR)
(ALIGNED
00h TO FFh
00h TO FFh
PD7:PD0 =
PD7:PD0 =
PDR
PDR
CLR
ETU
ETU
0.5 ETU
0.25 ETU
ATR. The ISO 7816-1997(3) specification recommends
in Section 4.3.4 that CLKx frequency switches be
made a) immediately after ATR or b) immediately after
a successful PPS exchange. The transmission parame-
ters F and D are respectively the clock-rate conversion
and baud-rate adjustment factors. The notations Fd
and Dd are used to represent the ‘d’efault values for
these parameters, which are Fd = 372 and Dd = 1.
The notation Fi and Di are used to represent the values
‘i’ndicated by the card within the TA(1) character of
ATR. If TA(1) is not present, then Fi, Di are set to the
default Fd, Dd values. The notation Fn and Dn repre-
sent values ‘n’egotiated during a successful PPS
exchange, which should be in the range Fd-Fi and Dd-
Di, respectively. During ATR, the default Fd, Dd values
shall apply. If the card comes up in negotiable mode
(i.e., TA(2) is absent from the ATR), then the Fd, Dd
SOFTWARE
1
0
MODE
EN
CLK
EN
CLK
EN
CLK
DETECTED COUNTER
FRACTIONAL ETU
FRAME-ERROR-
TOC COUNTERS
COUNTERS
10.5 ETU
TO 15 ETU
10.25 ETU
TO3, TO2,
TO1
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