Intel MPCBL0010 Onboard Power Supplies, 6.2 FWH1 Backup/Recovery Bios, Flash ROM Backup Mechanism

Feature Overview—MPCBL0010 SBC

2.2.6.2FWH1 (Backup/Recovery BIOS)

The FWH1 firmware hub stores the recovery BIOS. In the event of a checksum failure on the main BIOS operational code, the BIOS requests the BMC to switch firmware hubs, so that the board can boot up from FWH1 for recovery.

2.2.6.3Flash ROM Backup Mechanism

The on-board Intelligent Platform Management Controller (IPMC) manages which of the two BIOS flash ROMs is used during the boot process. The IPMC monitors the boot progress and can change the flash ROM selection and reset the processor.

The Intelligent Platform Management Controller sets the ID for both firmware hub (FWH) devices. The default state is to configure the main firmware hub (FWH) ROM device ID to be the boot device; the backup FWH is assigned the next ID. The backup FWH responds to the address range just below the main FWH ROM in high memory.

Boot accesses are directed to the FWH with ID = 0; unconnected ID pins are pulled low by the FWH device. In this way the IPMC can select which flash ROM is used for the boot process.

2.2.7Onboard Power Supplies

The main power supply rails on the MPCBL0010 SBC are powered from dual-redundant -48 V power supply inputs from the AdvancedTCA backplane power connector (P10). There are also dual redundant, limited current, make-last-break-first (MLBF) power connections.

2.2.7.1Power Feed Fuses

As required by the PICMG 3.0 specification, the MPCBL0010 SBC provides fuses on each -48 V power feed and on the RTN connections as well. The fuses on the return feeds are critical to preventing overcurrent situations if an ORing diode in the return path fails and there is a voltage potential difference between the A and B return paths.

2.2.7.2ORing Diodes and Circuit Breaker Protection

The two -48 V power sources are ORed together. A current limiting FET switch is connected between the ORed -48 V sources and the primary DC-DC converters. The FET switch provides three functions:

•A mechanism to electrically connect/disconnect the SBC to/from the two -48 V inputs.

•A soft-on function.

•An electronic over-current circuit breaker feature.

2.2.7.3Isolated -48 V to +12 V, 12 V Suspend, 5 V, 3.3 V Suspend, 1.8 V, and 1.5 V Converters

These converters provide DC isolation between the -48 V and -48 V return connections and all of the derived DC power on the MPCBL0010 SBC. A 12 V rail provides up to 10 A of current mainly for processor VRM and the two AdvancedMC slots. A 5 V output provides up to 2 A of current mainly for USB. The 3.3 V suspend provides the main 3.3 V when back end power is enabled. Up to 6 A of 3.3 V is provided when board is full on. The converter’s 1.8 V output provides up to 25 A of current, and the 1.5 V provides up to 18 A of current. The 12 V suspend and 3.3 V suspend outputs are always enabled. When the board is in the suspend state, no more than 10 W is drawn from the -48 V input (as specified in PICMG 3.0). All other outputs are enabled under IPMC control.

	Intel NetStructure® MPCBL0010 Single Board Computer
October 2006	Technical Product Specification
Order Number: 304120	21