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Functional Description
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3-17
3
can, however, assert machine check (MCP_) on double-bit error.
Table 3-8. Error Reporting
Error
Type
Single-Beat
/Four-Beat Read
Single-Beat Write
Four-Beat Write
Scrub
Single-Bit
Error
Terminate the
PowerPC
60x
bus
cycle normally.
Provide corrected
data to the
PowerPC
60x
bus
master.
Assert INT_ if so
enabled.
Terminate the
PowerPC
60x
bus
cycle normally.
Correct the data
read from DRAM,
merge with the
write data, and
write the
corrected, merged
data to DRAM.
Assert INT_ if so
enabled.
N/A
1
This cycle is not
seen on the
PowerPC
60x
bus.
Write corrected
data back to
DRAM if so
enabled.
Assert INT_ if so
enabled.
Double-Bit
Error
Terminate the
PowerPC
60x
bus
cycle normally.
Provide miss-
corrected, raw
DRAM data to the
PowerPC
60x
bus
master.
Assert INT_ if so
enabled.
Assert MCP_ if so
enabled.
Terminate the
PowerPC
60x
bus
cycle normally.
May or may not
perform the write
portion of the
read-modify-write
cycle to DRAM.
2
.
Assert INT_ if so
enabled.
Assert MCP_ if so
enabled.
N/A
1
This cycle is not
seen on the
PowerPC
60x
bus.
May or may not
perform the write
portion of the
read-modify-
write cycle to
DRAM.
2
.
Assert INT_ if so
enabled.
Triple- (or
greater)
Bit Error
Some of these errors are detected correctly and are treated the same as double-bit
errors. The rest could show up as “no error” or “single-bit error”, both of which
are incorrect.