Digital Equipment AlphaServer 1200, Service Manual

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4-50 Service Manual PRELIMINARY
3. When you have isolated the failing memory pair, determine which of the two
modules is bad. (You cannot do this if the operating system is Windows NT.)
Read the CPU FIL SYNDROME Register. If this register is non-zero, use the
ECC syndrome bits in Table 4-8 to determine which module had the single-bit
error.
Table 4-8 ECC Syndrome Bits Table
MDP Syndrome Values for Low-Order Memory
01 02 04 08 10 20 40 80 CE
CB D3 D5 D6 D9 DA DC 23 25
26 29 2C 31 13 19 4F 4A 52
54 57 58 5B 5D A2 A4 A8 B0
MDP Syndrome Values for High-Order Memory
2A 34 0E 0B 15 16 1A 1C E3
E5 E6 E9 EA EC F1 F4 A7 AB
AD B5 8F 8A 92 94 97 98 9B
9D 62 64 67 68 6B 6D 70 75