Bit-line Twisting Proposal Including Periodicity Version 3.0

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Bit-line Twisting ProposalIncluding
PeriodicityVersion 3.0

• Gary Waggoner
• April 11, 2008

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New CTL Syntax

• Add new BitLineTwistingRow construct
• BitLineTwistingRow specifies the row where
  bit-line twisting occurs (1twisting, 0no
  twisting)
• BitLineTwistingRow0 specifies twisting for row
  0. If rows are omitted, a repeating pattern is
  assumed. The pattern is assumed to be the
  difference between the last row specified and the
  first row specified.
• Each field in the BitLineTwistingRow represents a
  column (a bit). All columns (bits) must be
  specified. If a repeating pattern occurs, it can
  be described using the \r operator.

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Memory Architecture128 words, 4 bits, mux 8
(bitline twisting every cell)
Rows 0 thru 15
SA
SA
SA
SA
Bit 0
Bit 1
Bit 2
Bit 3
4
Alternative Solution (1st example)
MemoryPhysicalTopology // put all physical
infor in this block BitDistribution
1 ColumnMultiplexing 8 BitLineMirroring 1
// Ignore this for now // define Bit Line
Twisting BitLineTwisting // Define the
generic Data topology BitLineTwistingRow0
\2r 0000000011111111 // repeat to fill all 32
cols BitLineTwistingRow1 \32r 1 // repeat
to fill all 32 cols .. .. .. //
NOTE this example isnt periodic across rows.
All // BitLineTwistingRows have to be
specified // define Address and Data
Scrambling in a generic definition ScrambleDefini
tion SMap 1 TopologicalColumnAddress0
Add0 TopologicalColumnAddress1
Add1 .. .. Relation ..
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Memory Architecture128 words, 4 bits, mux 8
(bitline twisting every 3rd row)
Rows 0 thru 15
SA
SA
SA
SA
Bit 0
Bit 1
Bit 2
Bit 3
6
Proposed Solution (2nd example)
MemoryPhysicalTopology // put all physical
infor in this block BitDistribution
1 ColumnMultiplexing 8 BitLineMirroring 1
// Ignore this for now // define Bit Line
Twisting BitLineTwisting // Define the
generic Data topology BitLineTwistingRow0
\8r 0011 // repeat to fill all 32
cols BitLineTwistingRow3 \8r 1100 //
repeat to fill all 32 cols BitLineTwistingRow6
\8r 0011 // repeat to fill all 32 cols //
assume repeating BitLineTwistingRow pattern with
a periodicity of 6 // define Address and Data
Scrambling in a generic definition ScrambleDefini
tion SMap 1 TopologicalColumnAddress0
Add0 TopologicalColumnAddress1
Add1 .. .. Relation ..