73S1209F Maxim, 73S1209F Datasheet - Page 83

• Manufacturer Part Number: 73S1209F
• Description: The 73S1209F is a self-contained, SoC smart card reader IC that is an ideal solution for serially connected ISO 7816 design
• Manufacturer: Maxim

DS_1209F_004
V
A programmable timer is provided to set the time from activation start (setting the VCCSEL.1 and
VCCSEL.0 bits to non-zero) to when VCC_OK is evaluated. VCC_OK must be true at the end of this
timers programmed interval (tto in
is not true and the end of the interval (tto), the Card Event interrupt will be set, and a deactivation
sequence shall begin including clearing of the VCCSEL bits.
MSB
Rev. 1.2
OFFTMR.3 OFFTMR.2 OFFTMR.1 OFFTMR.0 VCCTMR.3 VCCTMR.2 VCCTMR.1 VCCTMR.0
CC
VccTmr.7
VccTmr.6
VccTmr.5
VccTmr.4
VccTmr.3
VccTmr.2
VccTmr.1
VccTmr.0
Stable Timer Register (VccTmr): 0xFE04
Bit
VCCTMR.3
VCCTMR.2
VCCTMR.1
VCCTMR.0
OFFTMR.3
OFFTMR.2
OFFTMR.1
OFFTMR.0
Symbol
VCC Off Timer – The bits set the delay (in number of ETUs) for
deactivation after the VCCSEL.1 and VCC SEL.0 have been set to 0. The
time value is a count of the 32768Hz clock and is given by tto =
OFFTMR(7:4) * 30.5μs. This delay does not affect emergency
deactivations due to VDD Fault or card events. A value of 0000 results in
no additional delay.
VCC Timer – VCCOK must be true at the time set by the value in these
bits in order for the activation sequence to continue. If not, the VCCSEL
bits will be cleared. The time value is a count of the 32768Hz clock and is
given by tto = VCCTMR(3:0) * 30.5μs. A value of 0000 results in no
timeout, not zero time, and activation requires that RDYST is set and RDY
goes high.
Figure
Table 77: The VccTmr Register
15) in order for the activation sequence to continue. If VCC_OK
0x0F
Function
73S1209F Data Sheet
LSB
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