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AlphaServer DS20 Service Manual
Table 3-3 Dcache Status Register
Name
Bits
Type
Description
Reserved
<63:5>
Reserved for Compaq.
SEO
<4>
W1C
Second error occured. When set, indicates that a
second Dcache store ECC error occurred within 6
cycles of the previous Dcache store ECC error.
ECC_ERR
_LD
<3>
W1C
ECC error on load. When set, indicates that a
single-bit ECC error occurred while processing a
load from the Dcache or any fill.
ECC_ERR
_ST
<2>
W1C
ECC error on store. When set, indicates that an
ECC error occurred while processing a store.
TPERR_P1 <1>
W1C
Tag parity error — pipe 1. When set, indicates that
a Dcache tag probe from pipe 1 resulted in a tag
parity error. The error is uncorrectable and results
in a machine check.
TPERR_P0 <0>
W1C
Tag parity error — pipe 0. When set, this bit
indicates that a Dcache tag probe from pipe 1
resulted in a tag parity error. The error is
uncorrectable and results in a machine check.
