HP Kayak XA-s02 Hardware Manual page 2

MaxiLife Hardware Monitoring Chip
MaxiLife is a hardware monitoring chip which is resident on the system
board. Its responsibility includes On/Off and reset control, status panel
management (Lock button, LEDs), hardware monitoring (temperature and
voltage), early diagnostics (CPU, DIMMs, PLLs, boot start), run-time
diagnostics (CPU errors, package intrusions), and other miscellaneous
functions (such as special OK/FAIL symbols based on a smiling face).
The integrated microprocessor includes a Synopsys cell based on Dallas
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"8052" equivalent, a 2 KB boot ROM, 256 bytes of data RAM, an I C cell, an
Analog-to-Digital (ADC) with 5 entries, and an additional glue logic for
interrupt control, fan regulation, and a status panel control.
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MaxiLife downloads its code in 96 milliseconds from an I C serial EEPROM.
The total firmware (MaxiLife 8051-code, running in RAM) size is 5 KB. As it
exceeds the 2 KB program RAM space, a paging mechanism will swap code
as it is required, based on a 512 byte buffer. The first 2 KB pages of firmware
code is critical because it controls the initial power on/reset to boot the
system. This initial page is checked with a null-checksum test and the
presence of MaxiLife markers (located just below the 2 KB limit).
If the boot block has been corrupted, the Firmware can start from its 'crisis'
block. To do this, set the System board switch 10 to the Closed position.
MaxiLife is partially replacing HP ASIC (Little Ben), and provides the neces-
sary hardware monitoring control. However, MaxiLife is not accessible in I/O
space or memory space of the system platform, but only through the SMBUS
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(which is a sub-set of the I C bus), via the PCI/ISA chipset (PIIX4E South
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Bridge). Its I C cell may operate either in Slave or Master mode, switched by
firmware, or automatically in case of 'Arbitration' loss.
As a monitoring chip, MaxiLife reports critical errors at start-up, and as such
is powered by Vstandby (3.3V) power. For MaxiLife to work correctly, the
PC Workstation must always be connected to a grounded outlet. This
enables the PC Workstation's hardware monitoring chip to be active, even if
the system has been powered off.
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