Service manual

5-44 AlphaServer 4000/4100 Service Manual
5.4 Troubleshooting IOD-Detected Errors
Step 1
Read the CAP Error Registers on both PCI bridges (F9E0000880 and FBE0000880).
If one or both of these registers shows an error, match the register contents with the
data pattern and perform the action indicated.
Table 5-3 CAP Error Register Data Pattern
Data Pattern Most Likely Cause Action
110x x00x x000 0000 0000 0000 000x xxxx RDSB - Uncorrectable ECC
error detected on upper QW of
MC bus (D127:64>)
Go to Step 2
101x x00x x000 0000 0000 0000 000x xxxx RDSA - Uncorrectable ECC
error detected on lower QW of
MC bus (D63:0>)
Go to Step 2
111x x00x x000 0000 0000 0000 000x xxxx RDS detected in both QWs Go t to Step 2
1001 1000 x000 0000 0000 0000 000x xxxx CRDB - Correctable ECC error
detected on upper QW of MC
bus (D127:64>)
Go to Step 2
1000 0000 x000 0000 0000 0000 000x xxxx CRDA - Correctable ECC error
detected on lower QW of MC
bus (D63:0>)
Go to Step 2
1001 1000 x000 0000 0000 0000 000x xxxx CRD detected in both QWs.
100x x10x x000 0000 0000 0000 000x xxxx NXM - Nonexistent MC bus
address
Go to Step 3
100x x01x x000 0000 0000 0000 000x xxxx MC_ADR_PERR - MC bus
address parity error
Go to Step 4
100x x00x 1000 0000 0000 0000 000x xxxx PIO_OVFL - PIO buffer
overflow
Go to Step 5
0000 0000 0000 0000 0000 0000 0001 1xxx PTE_INV - Page table entry is
invalid
Go to Step 6
0000 0000 0000 0000 0000 0000 0001 x1xx MAB - Master abort Go to Step 7
0000 0000 0000 0000 0000 0000 0001 xx1x SERR - PCI system error Go to Step 8
0000 0000 0000 0000 0000 0000 0001 xxx1 PERR - PCI parity error Go to Step 9