tda8007bhl/c3 NXP Semiconductors, tda8007bhl/c3 Datasheet - Page 27

• Manufacturer Part Number: tda8007bhl/c3
• Description: Double Multiprotocol Ic Card Interface
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Table 26 Description of CCRx bits
Clock switching constraints:
2003 Feb 18
f
In case of f
When switching from
same). When switching from
When switching from
frequency change on CLK (the fastest switching time is from
from
It is necessary to survey the bit CLKSW in register MSR before re-transmitting commands to the card.
Double multiprotocol IC card interface
int
2 to 0
is the frequency delivered by the internal oscillator
BIT
7
6
5
4
3
1
8
f
XTAL
CLK
to
= f
SYMBOL
1
2
XTAL
CC7
CC6
CST
f
SHL
SC
int
AC
or vice verse)
1
1
, the duty cycle must be ensured by the incoming clock signal on pin XTAL1
n
n
f
f
XTAL
XTAL
not used
not used
Stop HIGH or LOW. If bit CST = 1, then the clock is stopped at LOW level if bit SHL = 0,
and at HIGH level if bit SHL = 1.
Clock stop. In the case of an asynchronous card, bit CST defines whether the clock to
the card is stopped or not; if bit CST is reset, then the clock is determined by bits AC0,
AC1 and AC2.
Synchronous clock. In the event of a synchronous card, then contact CLK is the copy
of the value of bit SC; in reception mode, the data from the card is available to bit UR0
after a read operation of register URR; in transmission mode, the data is written on
the I/O line of the card when register UTR has been written to and remains unchanged
when another card is selected.
Alternating clock. All frequency changes are synchronous, thus ensuring that no
spikes or unwanted pulse widths occur during changes.
to
to
1
n
1
1
f
XTAL
2
2
f
AC2
f
int
int
0
0
0
0
1
1
1
1
or vice verse, only bit AC2 must be changed (bits AC1 and AC0 must remain the
or vice verse, a delay can occur between the command and the effective
or
1
2
f
int
to clock stopped or vice verse, only bits CST and SHL must be changed
AC1
0
0
1
1
0
0
1
1
27
1
2
f
XTAL
DESCRIPTION
AC0
to
0
1
0
1
0
1
0
1
1
2
f
int
or vice verse, the best for duty cycle is
(ASYNCHRONOUS CARD)
CLOCK FREQUENCIES
1
1
1
f
1
2
4
8
Product specification
XTAL
f
f
f
2
XTAL
XTAL
XTAL
f
TDA8007B
int