Service manual

The console and diagnostics sections include:
• A console read-only memory (ROM), which contains the code for
initialization, executing console commands, and bootstrapping the
system. The last line of the self-test display shows the ROM version.
In this example callout
1
indicates that the console ROM, ROM0, is
version V3.00.
• A diagnostic ROM, ROM1, which contains the power-up self-test and
extended diagnostics. The diagnostic ROM has the same version
number as the console ROM. In this example callout
2
indicates that
the diagnostic ROM is version V3.00.
• An electrically-erasable, programmable ROM (EEPROM), which
contains system parameters and boot code. You can modify the
parameters with the console SET commands. Patching console and
diagnostic code in the ROMs is done by reading the patches into a
special area of the EEPROM. The recommended procedure is described
in Section 4.18.
The last line of the self-test display shows two EEPROM version
numbers. The first number
3
indicates the format version of the
EEPROM. This version is changed only when the internal structure
of the EEPROM is modified.
The second number
4
is the revision of ROM patches that have been
applied to the EEPROM. The major number in this revision (before the
decimal point) corresponds to the major number of the ROM revision
1
.
The minor number indicates the actual patch revision. In this example,
the EEPROM has not been patched for console ROM V3.00.
• A system support chip (RSSC) that includes support for external ROM/
EEPROM, 1 Kbyte of battery-backed-up RAM, console terminal UARTs,
bus reset logic, interval timer, programmable timers, time-of-year
(TOY) clock, bus timeout, and halt arbitration logic.
<REFERENCE>(XRP) Scalar Processor 4–9