Technical data

Functional Description
MVME2502 Installation and Use (6806800R96B)
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4.4.1 Real Time Clock
The MVME-2502 implements a Maxim DS1337 RTC to maintain seconds, minutes, hours, day,
date, month, year accurately. The INT_A pin of the DS1337 is connected to the CPU GPIO[1]
pin to allow the DS1337 to generate interrupts to the CPU. Access to the DS1337 is provided
via the I2C port 0 from the CPU and responds to a base I2C address of $D0.
The MVME2502 provides a socketed 48mAh primary battery to power the RTC when the
module is out of service.
4.4.2 P2020 Internal Timer
The processor's internal timer is composed of eight global timers divided into two groups of
four timers each. Each time has four individual configuration registers and they cannot be
cascaded together.
4.4.3 Watchdog Timer
The onboard CPLD provides programmable 16-bit watchdog timers. It has a 1 ms resolution
and generates a board reset when the counter expires. Interrupt is generated to the processor
when this occurs. Default value is 60 seconds.
4.4.4 CPLD Tick Timer
The MVME2502 supports three independent 32-bit timers that are implemented on the CPLD
to provide fully programmable registers for the timers.
4.5 Ethernet Interfaces
The MVME2502 has three eTSEC controllers. Each one supports RGMII, GMII, and SGMII
interface to the external PHY. All controllers can only be utilized when using the RGMII
interface. Using the GMII allows only up to two usable controllers.