Digital Equipment DECstation 5000/100 Series, Руководство по обслуживанию

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Error Exception Program Counter (Error EPC) (R4000 Only)
The Error EPC register is similar to the EPC register, but it
is used on ECC and parity error exceptions. It is also used to
store the PC on Reset, Soft Reset and NMI exceptions. The
address may be either:
the virtual address of the instruction that caused the
exception, or
the virtual address of the immediately preceding branch or
jump instruction when that address is in a branch delay
slot.
There is no branch delay slot indication for the ErrorEPC
register The ErrorEPC register has the following format.
31 0
+--------------------------------------------------------+
|
ErrorEPC |
+--------------------------------------------------------+
32
Configuration Register (R4000 Only)
The Configuration Register (Config) specifies various
configuration options selected on R4000 processors. Some
configuration options, as defined by Config bits 31...6, are set
by the hardware during reset, and are included in this register
as read-only status for software. Other configuration options
are read/write (defined by Config bits 5..0) and controlled
by software; on reset these fields are undefined. The Config
register has the following format:
31 12 11 9 8 6 5 4 3 2 0
+-------------------------------+----+----+--+--+--+----+
|
Hardware Parameters | IC | DC |IB|DB|CU| K0 |
+-------------------------------+----+----+--+--+--+----+
3 3 1 1 1 3
Bits 31..12 indicate the setting of hardware parameters
which are loaded from the serial ROM on the daughter card.
For more information on these bits refer to the MIPS R4000
Microprocessor User’s Manual.
E–14 CPU and System Registers