OCPRF100 MP Server System Technical Product Specification

Revision 1.0

10.2.3.5System Event Log (SEL)

The system event log (SEL) serial EEPROM (which resides on the OCPROF100 I/O carrier on

the BMC’s private I2C bus) can be accessed by the front panel’s private bus under certain condi- tions. This feature has been added to allow access when main power is down.

When the I2C_CEL_CONNECT_FPC signal is asserted, the serial EEPROM is connected electrically to the FPC’s private I2C bus and is powered off of the 5 V standby supply.

When the I2C_CEL_CONNECT_BMC signal is asserted, the serial EEPROM is connected electrically to the I/O’s private I2C bus and is powered off of the +3.3 V supply.

When both the I2C_CEL_CONNECT_FPC and the I2C_CEL_CONNECT_BMC signals are asserted, the 5 V standby, +5 V, and the +3.3 V supplies are connected together. Firmware provisions prevent this scenario from happening.

An additional consideration is the BMC on power-up. A firmware mechanism is required to tell the BMC when this device is available.

It is required that the BMC’s I2C bus be static between 0 and 20 ms after the rising edge of the I2C_CEL_CONNECT_BMC signal.

Upon power-up, the I2C_CEL_CONNECT_BMC signal is asserted and the I2C_CEL_CONNECT_FPC is deasserted.

10.2.4Front Panel Indicator LEDs

The POWER_FAIL LED is under the control of the FPC. When the FPC asserts (high) the POWER_FAIL_LED_CMD signal, the LED becomes illuminated. This LED is off when deas- serted and during an FPC reset. This LED is powered off of 5 V standby so it can be illuminated even when +5 V is invalid.

The DRIVE_FAIL_LED is an indication of hard drive failure. It is illuminated when the

DRIVE_FAIL_LED_CMD signal is asserted (high). It is off when this signal is deasserted (low) and during an FPC reset.

The POWER_GOOD_LED is an indication of good DC power in the system. It is illuminated when the POWER_GOOD_LED_CMD signal is asserted (high). It is off when this signal is deas- serted (low) and during an FPC reset.

The FAN_FAIL_LED is under the control of the BMC. The FPC queries the BMC for system fan fail status. It illuminates when the FAN_FAILED_L signal is asserted (low) from the BMC. It is an indication of system cooling failure. Additionally, there is an LED associated with each fan. These LEDs are located adjacent to each individual fan to provide an indication of which of the six system fans has failed. These LEDs are driven by the FPC.

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