XC3S100E Xilinx Corp., XC3S100E Datasheet - Page 95

• Manufacturer Part Number: XC3S100E
• Description: Spartan-3e Fpga Family Complete Data Sheet
• Manufacturer: Xilinx Corp.

memory locations. After the FPGA completes configuration,
the application initially loaded into the FPGA performs a
board-level or system test using FPGA logic. If the test is
successful, the FPGA then triggers a MultiBoot event, caus-
ing the FPGA to reconfigure from the opposite end of the
In another potential application, the initial design loaded into
the FPGA image contains a “golden” or “fail-safe” configura-
tion image, which then communicates with the outside
world and checks for a newer image. If there is a new con-
figuration revision and the new image verifies as good, the
“golden” configuration triggers a MultiBoot event to load the
new image.
When a MultiBoot event is triggered, the FPGA then again
drives its configuration pins as described in
DS312-2 (v3.6) May 29, 2007
Product Specification
First Configuration
Parallel Flash PROM
Di agnostics
Application
Application
R
User Area
General
FPGA
FPGA
Figure 60: Use MultiBoot to Load Alternate Configuration Images
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0
> 300 ns
Table
58. How-
STARTUP_SPARTAN3E
GSR
GTS
MBT
CLK
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Flash PROM memory. This second configuration contains
the FPGA application for normal operation.
Similarly, the general FPGA application could trigger
another MultiBoot event at any time to reload the diagnos-
tics design, and so on.
ever, the FPGA does not assert the PROG_B pin. The sys-
tem design must ensure that no other device drives on
these same pins during the reconfiguration process. The
FPGA’s DONE, LDC[2:0], or HDC pins can temporarily dis-
able any conflicting drivers during reconfiguration.
Asserting the PROG_B pin Low overrides the MultiBoot fea-
ture and forces the FPGA to reconfigure starting from the
end of memory defined by the mode pins, shown in
Table
57.
Reconfigure
Second Configuration
P arallel Flash PROM
Di agnostics
Application
Application
User Area
General
FPGA
FPGA
Functional Description
DS312-2_51_103105
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