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82815 GMCH
R
Datasheet
167
6.2.
XOR Tree Initialization
6.2.1.
Chain [1:6] Initialization
On chains [1:6], all that is required to prepare the device for XOR chain testing is to pull SRAS# low
prior to deasserting RESET#. The following sequence will put the GMCH into XOR testability mode:
1. Deassert RESET# high and assert SRAS# low
2. Assert RESET# low; maintain SRAS# low
3. Deassert RESET# high; maintain SRAS# low
4. RESET# must be maintained high for the duration of testing.
No external clocking of the GMCH is required for testing these chains.
6.2.2.
Chain [7:8] Initialization
On chains[7:8], all that is required to prepare the device for XOR chain testing is to pull SMAA2 low
prior to deasserting RESET#, then set LTVCK high and LTVDATA[11:6] to [101101] (1 means high
and 0 means low), follow other LTVCK high and LTVDATA[11:6] to [100011]. The following
sequence puts the GMCH into XOR testability mode for Chain[7:8] only:
1. Deassert RESET# high and assert SMAA2 low
2. Assert RESET# low; maintain SMAA2 low
3. Deassert RESET# high; maintain SMAA2 low
4. Deassert LTVCK low and assert LTVDATA[11:6] to [101101]
5. Assert LTVCK high; maintain LTVDATA[11:6] to [101101]
6. Deassert LTVCK low; maintain LTVDATA[11:6] to [101101]
7. Deassert LTVCK low and assert LTVDATA[11:6] to [100011]
8. Assert LTVCK high; maintain LTVDATA[11:6] to [100011]
9. Deassert LTVCK low; maintain LTVDATA[11:6] to [100011]
10. RESET# must be maintained high for the duration of testing
No external clocking of the GMCH is required for testing these chains.