3-14
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Falcon ECC Memory Controller Chipset
3
Note that the Falcon pair does not assert TEA_ on double-bit errors. In fact,
the Falcon pair does not have a TEA_ signal pin and it assumes that the
system does not implement TEA_. The Falcon can, however, assert
machine check (MCP_) on double-bit error.
Note
No opportunity for error since no read of DRAM occurs during a
four-beat write.
Table 3-6. 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.
Do not perform the write
portion of the read-
modify-write cycle to
DRAM.
Assert INT_ if so
enabled.
Assert MCP_ if so
enabled.
N/A
1
This cycle is not seen on
the PowerPC 60x bus.
Do not perform the
write portion of the
read-modify-write cycle
to DRAM.
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.