DESIGN OF A CUSTOM ASIC INCORPORATING CAN™ AND 1 ...

6.2 Verification of Combined Prototype System
To verify proper operation of the 1 – Wire® and CAN combined prototype system,
several test cases are executed, utilizing both regular and overdrive 1 – Wire® communication
speeds. For all tests, the hardware used, shown in Figure 6.2, includes the following
components: three DS1996 – 64Kb Memory iButtons [83], DS1402-BR8+ 1 – Wire®
Network Cable [80], DS1401-4 Front-Panel iButton Holder [81], and two CAN nodes as
described in Section 5.3.20. The reason for using the DS1996 64Kb Memory iButtons is that
the DS1996 is the largest memory iButton currently in production, and provides 65,536 bits of
read/write nonvolatile memory partitioned into 256-bit pages for packetizing data. The
equivalent EPROM, DS1986 [99], could just as easily have been used as a suitable replacement
except the product is no longer available and therefore is not recommended for new designs.
However, the DS1977 [93] could be used as a substitute, especially if security were an issue and
password protection were required. Both tests are compiled and simulated using Altera Quartus
II 9.1 (32-bit) and ModelSim Altera Starter Edition 6.6c software on a PC executing Windows
XP Service Pack 3. All tests are performed extensively while trying to cover all possible
combinations of inputs and outputs. The source code for all modules, testbench code, and
simulation results are located on the DVD included with this work.
Figure 6.2 1 – Wire® & CAN Combined Prototype System.
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