73S1209F Maxim, 73S1209F Datasheet - Page 25

• 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
The master clock control register enables different sections of the clock circuitry and specifies the value
of the VCO Mcount divider. The MCLK must be configured to operate at 96MHz to ensure proper
operation of some of the peripheral blocks according to the following formula:
Mcount is configured in the MCLKCtl register must be bound between a value of 1 to 7. The possible
crystal or external clock frequencies for getting MCLK = 96MHz are shown in Table 11.
Master Clock Control Register (MCLKCtl): 0x8F
The MPU clock that drives the CPU core defaults to 3.6923MHz after reset. The MPU clock is scalable
by configuring the MPU Clock Control register.
Rev. 1.2
MCLKCtl.7
MCLKCtl.6
MCLKCtl.5
MCLKCtl.4
MCLKCtl.3
MCLKCtl.2
MCLKCtl.1
MCLKCtl.0
Bit
MCLK = (Mcount * 2 + 4) * F
MSB
HSOEN
Symbol
HSOEN
MCT.2
MCT.1
MCT.0
KBEN
SCEN
Table 11: Frequencies and Mcount Values for MCLK = 96MHz
–
–
KBEN
High-speed oscillator disable. When set = 1, disables the high-speed crystal
oscillator and VCO/PLL system. Do not set this bit = 1.
1 = Disable the keypad logic clock.
1 = Disable the smart card logic clock.
This value determines the ratio of the VCO frequency (MCLK) to the high-
speed crystal oscillator frequency such that:
MCLK = (MCount*2 + 4)* F
MCLK = (2*2 + 4)*12.00MHz = 96MHz.
SCEN
Table 12: The MCLKCtl Register
XTAL
= 96MHz
F
XTAL
12.00
–
9.60
8.00
6.86
6.00
(MHz)
0x0A
–
XTAL
Mcount (N)
. The default value is MCount = 2h such that
MCT.2
Function
2
3
4
5
6
MCT.1
MCT.0
73S1209F Data Sheet
LSB
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