73S8014RT TERIDIAN [Teridian Semiconductor Corporation], 73S8014RT Datasheet - Page 20

• Manufacturer Part Number: 73S8014RT
• Description: Smart Card Interface
• Manufacturer: TERIDIAN [Teridian Semiconductor Corporation]

3.8 Fault Detection and OFF
There are two different cases that the system controller can monitor the OFF signal: to query regarding the card
presence outside card sessions, or for fault detection during card sessions.
Outside a card session: In this condition, CMDVCC% and CMDVCC# are always high, OFF is low if the card is not
present, and high if the card is present. Because it is outside a card session, any fault detection will not act upon
the OFF signal. No deactivation is required during this time.
During a card session: CMDVCC% or CMDVCC# is/are always low, and OFF falls low if the card is extracted or if
any fault detection is detected. At the same time that OFF is set low, the sequencer starts the deactivation
process.
Figure 7
session and outside the card session:
session and outside the card session:
3.9 I/O Circuitry and Timing
The state of the I/O pin is low after power on reset and it goes high when the activation sequencer turns on the
I/O reception state. See the
state of I/OUC is high after power on reset.
Within a card session and when the I/O reception state is turned on, the first I/O line on which a falling edge is
detected becomes the input I/O line and the other becomes the output I/O line. When the input I/O line rising
edge is detected then both I/O lines return to their neutral state.
Figure 8
delay between the I/O signals is shown in
20
shows the timing diagram for the signals CMDVCC% or CMDVCC#, PRES, and OFF during a card
shows the state diagram of how the I/O and I/OUC lines are managed to become input or output. The
Figure 7: Timing Diagram – Management of the Interrupt Line OFF
Activation Sequence
Figure
9.
section for details on when the I/O reception is enabled. The
OFF during a card
Rev. 1.0