This assignment should be done in cooperation with your partners. This
is the design you will work on together as a group from now until the
end of the term.
(Obviously, since this assignment is the basis of
your design review, it must be completed on time.)
To the description of your machine, add the CALL, RET, IRETD,
CLD, STD, NOT, CMPXCHG, and
REPE SCAS instructions, and the logic necessary to
initiate exceptions and interrupts. The REPE SCAS will require you to
implement the repeat prefix.
Implement a set of segment limit registers that will be initialized in your
behavioral Verilog.
Implement the segment limit checking and the
generation of an exception when the segment limit is exceeded. To
test this functionality you (not your machine) will need to create an
Interrupt Descriptor Table in memory, as would be done by the
operating system in real life. Please hand in hard copies of
everything created to implement this functionality.
Note: Some of this is going to require additional internal registers and/or additional bits specified in existing internal registers.
Hand in the schematics created.
Design an external bus interface. (You will need this to handle external interrupts, memory accesses, and I/O.) This should include a description of bus signals and bus protocols.
Hand in a description of this bus interface.
Construct a block diagram for the machine that you intend to design and simulate this semester. This should include the major functional blocks (e.g. Data Path, Control, I/O components, Cache Memory, Main Memory, Level 1 Virtual Address Translation, Memory Protection etc.), and their interconnections. Be as detailed as you feel is necessary.
Hand in the block diagram.
Construct a detailed schedule for the design of your machine. Estimate how much time you expect to spend designing, simulating, and debugging each component on the Verilog system. Allow yourself as much debugging time as possible. As time goes by, you'll be able to draw a large schematic in a single evening, but the test/debugging/re-simulate cycle can be extremely time consuming. It will be advantageous to leave some time at the end for critical path analysis and redesign.
Please use a Gantt chart to represent your schedule, as shown below:
taskA | xxxxxxxx
taskB | xxxxxxxxx
taskC | xxxxxxxxx
... |
---------------------------------
| time ->
In your schedule, task{A, B, C} should be reasonably detailed descriptions of what you need to do to complete the task. Also, please note the dependencies between tasks and the division of labor between group members.
Hand in the schedule (no longer than one page).
Coordinate with your partners and sign up for an initial design review. This will take place on March 3rd and 4th in POB 6.336 unless otherwise notified. They will take up to 45 min each. A sign up sheet will be posted on Professor Patt's office door (POB 6.252) some time before the due date of this assignment. All members of your group must attend the first design review. If no time slot is good for the members of your group, please email the TAs and we will make other arrangements.
Please, make 4 copies of all documents to make the project review easier.