DDR MemBIST
Table 11-1. MemBIST Feature Summary (Sheet 2 of 2)
Feature
Feature Description
Failure data access
Failure data logged and accessible using FBD, JTAG or SMBus
Logging may be delayed to capture later failures
Algorithms Provided
Algorithms operate over a specified address range with a fixed data pattern of 0xA only
Notation for algorithm definitions:
^ = increasing address from start to end
v = decreasing address from end to start
W / R = Write / Read and check
D / I = Data / Inverted Data
number = sequence of events
(x, y) = for each address, first x is applied, then y, before continuing to next address
Scan
^ (WD ); ^(RD ); ^ (WI ); ^ (RI )
1 2 3 4
Init
^ (WD )
1
Mats+
MarchC–
^(WD ); ^(RD , WI ); v(RI , WD );
1 2 3 4 5
^(WD ); ^(RD , WI ); ^(RI , WD );
1
2
3
4
5
v(RD , WI ); v(RI , WD ); v(RD );
6
7
8
9
10
Read and check
Error Logging
Error logging
^(RD );
1
Pass / fail indicator
Log up to 5 failing addresses
Record up to 4 sets of 144-bit failure data
144-bit failure data bit location accumulator marking bit failures
through entire test
11.3
MemBIST Operation
11.3.1
Fundamental Operations
The MemBIST logic provides a number of operational modes which can be combined in
various ways to provide a large number of useful combinations. For example, there is a
mode in which it is possible to select address incrementing first by column and then by
row, or the opposite of this. There is also a mode to dynamically invert every other
address, which toggles all address lines to opposite states. These two independent
modes can be combined to test a bank by toggling row address lines to opposite states
or by toggling column address lines to opposite states. Limits on combinations are
mentioned where they exist.
MemBIST also provides a number of complete operations which it can perform.
MemBIST operations can be characterized as a task which MemBIST carries out
automatically after being programmed for the task. The operation begins when
MBCSR:start is set by the user and ends when MemBIST clears this same bit.
MemBIST operations include built-in algorithms and fundamental commands.
MemBIST built-in algorithms consist of complete testing schemes which are
implemented in MemBIST and which carry out complete tests for meeting specific
testing objectives. They accomplish their testing completely under automatic control
once the operation is started.
Intel® 6400/6402 Advanced Memory Buffer Datasheet
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INTEL [ INTEL ]
