EP80579 Datasheet, PDF (1340/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
36.6
• Clock frequency of 40 MHz
IEEE 1588 Time Synchronization Hardware Assist
In a distributed control system containing multiple clocks, individual clocks tend to drift
apart. Some kind of correction mechanism is necessary to synchronize the individual
clocks to maintain global time, which is accurate to some requisite clock resolution. The
IEEE 1588 standard for a precision-clock-synchronization protocol for networked
measurement and control systems can be used for this purpose.
The IEEE standard defines several messages that can be used to exchange timing
information. The hardware-assist logic required to achieve precision clock
synchronization using the IEEE 1588 standard is left to implementation.
The time-synchronization logic monitors the internal MII/GMII signals on two of the
three Gigabit Ethernet interfaces. Additionally, this block monitors both CAN interfaces.
An interrupt signal to the IA-32 core is generated when any of the following conditions
occur and are enabled:
• Target time expiration
• Auxiliary Master Mode snapshot is taken
• Auxiliary Slave Mode snapshot is taken
The System Time and Target Time registers are both 64 bits wide. When the system
time is greater than or equal to the target time, the target time expiration condition will
set. An interrupt enable mask must be set to allow the target time interrupt to pass to
the core.
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Intel^® EP80579 Integrated Processor Product Line Datasheet
1340
August 2009
Order Number: 320066-003US