Appeal No. 2006-2217
Reexamination Control Nos. 90/006,789 and 90/007,420
and performance constraints that differ radically from the
general purpose systems described in "286/100" and
"2164A" (Br48-50). It is argued (Br49):
Bruce discusses a method for page boundary detection
that is specific to a graphics system for raster display
refresh. Bruce at col. 1:7-10. In fact, Bruce explicitly
teaches away from considering page mode memory access in
graphics/raster display applications generally, explaining:
[P]age mode has not heretofore been considered useful
in raster display refresh memory systems because of the
low probability that memory locations which need to be
accessed sequentially by the graphics computation
device will fall on the same "page" since the "page"
extends only in one dimension of the display memory.
Id. at col. 2:17-24.
A reference is analogous prior art if it is in the field of
the inventor's endeavor or reasonably pertinent to the particular
problem with which the inventor was concerned. See
Deminski, 796 F.2d at 442, 230 USPQ at 315. The scope of the
prior art is a finding of fact. The field of inventor's endeavor
is memory controllers for "page mode" access of DRAMs in a system
having "requesting agents and "replying agents" connected to a
"system bus," in particular, a Multibus II system. Bruce
describes memory controllers for page mode DRAMs (e.g., Fig. 3)
and is within the inventor's field of endeavor. The particular
problem the inventor was concerned with in claims 6 and 17 was
crossing a page (row) boundary during a page mode of operation.
Bruce discloses apparatus for detecting and crossing a page
boundary in "page mode" memory accesses as part of its overall
invention and thus addresses the same problem facing the
inventor. Bruce teaches the same solution recited in claims 6
and 17. Bruce is within the scope of the prior art.
Bruce does not state that the method for page boundary
detection and crossing is limited to the disclosed graphics
system. The page boundary detection and crossing technique
described as a general technique (see col. 3, lines 29-51) and
can be applied to any page mode memory system. Bruce's statement
that page mode has not been considered to be useful in raster
display memory systems does not constitute a teaching away from
the use of the page mode, in general. Bruce teaches that the
page mode has the advantage of allowing memory locations on the
same page to be accessed at a significantly higher speed than a
normal access to an arbitrary memory location (col. 2, lines
12-17), which is motivation for using a page mode. Bruce also
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