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22 Sept 2016
v1.1
2.15 MAC ID – UNI/O EEPROM (7Z015/30 only)
In addition to the MAC ID EEPROM, a second 2Kb MAC ID UNI/O® EEPROM with EUI-48
Node Identity (Microchip PN: 11AA02E48) is used to store a MAC address for a SFP+ Ethernet
module. This device is only accessible with a 7015/30 SOM. The device allows a user ID to be
written at location 0x00 to 0xC0. The devices’ remaining memory is programmed at the factory
with a globally unique node address stored in the upper half of the array. This address (0xC0 to
0xFF) is permanently write protected.
Figure 14 – MAC UNI/O EEPROM
2.16 Real Time Clock – Maxim DS3231MZ
RTC I2C ADDR:
0xD0
A Maxim DS3231 I2C RTC IC at address
0xD0
has been placed on the board to allow for clock
and calendar functions. The RTC has a built in oscillator so an external device is not required.
The interface is level translated using U11, a TCA9517 IC and attached to the HDMIO I2C bus.
The RTC has a battery backup using a BHX1-1025 battery holder.
The RTC also has an open-drain, active-low interrupt or 1Hz square-wave output multifunction
pin connected to RTC_INT. The interrupt function can be programmed to trigger upon a match
between the timekeeping registers and either of the alarms. Refer to JX3 pin table for the pin
assignments.
Figure 15 – RTC connections