1076.1 Table-driven Modeling Subcommittee
April 9, 2012 – 8am PST – 5pm CET
Joachim Haase
Agenda
 Call to order
 Volunteer for minutes
 Approval of agenda
 Review and approve minutes from the last meeting
 Status of reference implementation
 Discussion on open questions concerning a standard proposal
 Next meeting
 AOB
 Adjourn
Approve minutes from January 30, 2012 meeting
 Minutes available in the Table-driven modeling member-only area
http://www.eda.org/twiki/bin/view.cgi/P10761/TDMMtgMinutesJan3012
 Review of IEEE Patent policy
http://www.eda.org/twiki/pub/P10761/WebHome/pat-slideset.pdf
Action items from the last meeting
 Update of the reference implementation using VHDL 2008
 Contact to ISAC (VHDL) concerning the declaration of types
TABLE_DATA_REAL and TABLE_DATA_COMPLEX (opac ? or not).
Status of reference implementation (1)
 Updates as proposed on the last meeting
 For PREPARE_TABLE_DATA functions that read data from a file, an
additional argument and corresponding type shall be provided. File formats
(such as Touchstone, ...) shall be described by this parameter.
 The DEPENDENT_SELECTOR in the case of complex-valued onedimensional interpolation shall point to a group of two columns that describe
a complex number.
 A type REAL_MATRIX (available in VHDL 2002) instead of
REAL_VECTOR_ARRAY (only available in VHDL 2008) shall be used to
provide data for multi-dimensional interpolation.
Status of reference implementation (2)
impure function PREPARE_TABLE_DATA (
FILE_NAME
: STRING;
X_UNIT
: X_UNIT_TYPE
Y_FORMAT
: Y_FORMAT_TYPE := RI;
METHOD
: INTERPOLATION_METHOD := TDM_PWL;
LEFT
: EXTRAPOLATION_METHOD := TDM_ERROR;
RIGHT
: EXTRAPOLATION_METHOD := TDM_ERROR;
:= GHz;
DEPENDENT_SELECTOR : POSITIVE
SEPARATOR
:= 1;
: CHARACTER := ' '
)
return TABLE_DATA_COMPLEX;
DEPENDENT_SELECTOR points to a
group of two values
Status of reference implementation (3)
--/**
-- Type to describe data points for multi-dimensional intrepolation.
--*/
type
REAL_MATRIX is array (NATURAL range <>, NATURAL range <>) of REAL;
function PREPARE_TABLE_DATA (
X
: REAL_MATRIX;
Y
: REAL_VECTOR;
METHOD : INTERPOLATION_METHOD_VECTOR;
LEFT
: EXTRAPOLATION_METHOD_VECTOR;
RIGHT
: EXTRAPOLATION_METHOD_VECTOR)
return TABLE_DATA_REAL;
X describes the M N-dim points
(X(0,0), X(0,1), …, X(0,N-1)
…
(X(M-1,0), X(M-1,1), …, X(M-1,N-1)
Status of reference implementation (4)
 No proposal for the requirement:
For PREPARE_TABLE_DATA functions that read data from a file, an
additional argument and corresponding type shall be provided. File formats
(such as Touchstone, ...) shall be described by this parameter.
Documentation
 Starting point for final documentation available
http://www.eda.org/twiki/pub/P10761/ProjectTableDrivenModeling/tdm_v0.9_doc_proposal.pdf
 Proposal for the declaration of record structures TABLE_INTERPOLATION_PKG header
type TABLE_DATA_REAL is
record
N
: INTEGER;
-- dimension of interpolation
-- tool dependent implementation possible
end record;
type TABLE_DATA_COMPLEX is
record
N
: INTEGER;
-- dimension of interpolation
-- (only 1 is supported)
-- tool dependent implementation possible
end record;
Proposal for action items
 Update of VHDL 2008 implementation
 Review of code, test cases and documentation
Next meeting
 Monday, May 7, 2012 – 8am PDT (UTC-7) = 5pm CEST (UTC+2)