ZiLOG System 8000 Hardware Reference Manual page 349

HRM 2ilog HRM
"undetected" error message is displayed. If the NMI occurs,
the ECC error count register is checked to verify that the
ECC recorded the 2-bit error. If not, an "unreportl=d" error
message is displayed.
Test 2 repeats
64 K
times during each lap of ECCTEST. Each
repetition is done using a different data pattern and a dif-
ferent pair of corrupted bits.
Test 3 is an ECC memory test. Every double-word location in
segments 1 through maxseg is tested using three patterns.
The patterns are:
0, Ox01090000 and Ox00000106
For each pattern, the correct pattern is written to the
location and the correct check byte is written to the
check-byte register. Then the location is read with memory
correction enabled. If the data read does not match the
data written, a data error message is displayed. If the
data matches the original, the ECC error count register is
checked to see if the ECC recorded error correction
occurred. If so, a "corrected" error message is displayed.
ERROR MESS,AGES
Te st 1:
SB--orig: xxxxxxxx-cc, wrote: xxxxxxxx-cc, read: xxxxxxxx-cc
where xxxxxxxx
=
the data pattern (hex)
cc
=
the check-byte (he~)
SB
=
"SINGLE BIT" ;
SB--Corrected 1-bit error unreported: count
=
cccc, report
=
xxxx
where cccc
=
the test's count of 1-bit errors (hex)
xxxx
=
the error count register content (hex)
Test 2:
TB--orig: xxxxxxxx-cc, wrote: xxxxxxxx-cc, read: xxxxxxxx-cc
where xxxxxxxx
=
the data pattern (hex)
cc
=
the check-byte (hex)
TB
=
"TWO BIT"
Detected 2-bit error unreported: count
=
cccc, rE~port
=
xxxx
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2ilog
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