Compaq AlphaServer DS20, Руководство по обслуживанию

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System Overview 1-35
Figure 1-18 is a block diagram of the TIG bus implemented through the TIG chip.
Three system functions are carried out on this bus.
Flash ROM
The flash ROM containing the diagnostics, fail-safe loader, and console firmware sits
on the TIG bus. (This is different from the AS 1200 where the flash ROM sat on the
I
2
C bus.) Still a good deal of logic has to function for the diagnostics to run.
Configuration Registers
Registers on the bus include interrupts, module information, and clock information.
Interrupts
System interrupts are passed through the TIG bus to the C-chip. The bus connects
directly to PCI slots and to onboard devices.