LAB 6 WORKSHEET
1. What process translates the HDL (hardware description language) into a
netlist?
The FPGA Express Synthesis Process is what translates the HDL (hardware description
language) into a netlist.
2. Give two examples of projects that are good for FPGAs.
FPGA architecture is good for projects that require a large number of inputs
and outputs but are not adversely affected by the FPGAs need to be programmed
after each power cycle. Examples of projects that are good for FPGAs
include missile technology and modem & digital signal processing.
3. Give two examples of projects that are good for CPLDs.
CPLDs are good for projects that require wide logic, for example memory interfaces,
low-power applications, bus control, and mp3 players.
4. What does an accumulator do?
Accumulators are a major portion of any large digital logic or DSP project.
Accumulators are very similar to counters. Accumulators differ from counters
in the nature of the operands of the add and subtract operation. An accumulator
can be up, down, or updown. Accumulators can be compared to a file cabinet,
in terms of operation.
5. What is the difference between a CLB and an IOB?
CLBs (Configurable Logic Blocks) are inside the device and are surrounded by
the IOBs (Input/ Output Blocks).
6. Why is it good to be able to reuse sections of code for different projects?
Reusing code for different projects reduces time spent on development and allows
for more time to focus on implementing the design via the actual components.
Reusing code is also good as it keeps the code compact and portable and makes
the resulting project easier to read (functions handle large parts of the program
and therefore keeps the main compact and easy to read).
7. An FPGA loses its programming when the power is removed. Think of
a reason or application where this would be a good thing (think militarily).
An application that would be good for FPGAs is the circuitry of missiles that
are deployed into hostile territory. The advantage is that if the missile were
unable to detonate, the program would still be lost and therefore irretrievable
upon the loss of power. This would help prevent the program code from being
intercepted by the adversary.
8. In floorplanner, on a SpartanXL, what three things make up a CLB?
CLBs are made up of 1) Flip-Flops, 2) Function Generator, and 3) Tristate Buffers.