Controlling Design Implementation
CPLD Schematic Design Guide
3-29
where newgroup is a newly created group that consists of existing
groups created via TNMs, predefined groups, or other TIMEGRP
attributes.
Mentor Users -- You must specify a leading equal sign (=) when
defining TIMEGRP attributes, for example, =newgroup. The
preceding equal sign lets Mentor know that this is a user-defined
attribute. Refer to the Mentor Graphics Interface/Tutorial Guide for more
information.
TIMEGRP attributes reside in the TIMEGRP primitive, as illustrated
in the "TIMEGRP Primitive" figure. Once you create a TIMEGRP
attribute definition within a TIMEGRP primitive, you can use it in the
TIMESPEC primitive. Each TIMEGRP primitive can hold up to eight
group definitions. Since your design might include more than eight
TIMEGRP attributes, you can use multiple TIMEGRP primitives.
Figure 3-7
TIMEGRP Primitive
You can place TIMEGRP attributes in either of two places: in the
TIMEGRP primitive on the schematic as discussed in this section or
in a constraints file (UCF or NCF). The syntax for specifying TNMs in
a UCF or NCF constraints file is described in the "Attributes"
appendix.
You can use TIMEGRP attributes to create groups using the following
methods:
·
Combining multiple groups into one
·
Creating groups by exclusion
X4330
TIMEGRP
some_ffs=flips:flops
Summary :
Controlling Design Implementation CPLD Schematic Design Guide 3-29 where newgroup is a newly created group that consists of existing groups created via TNMs, predefined groups, or other TIMEGRP attributes.
Tags :
primitie,attributes,groups,mentor,use,design,tnms,eight,figure,guide,group,ucf,equal