The most important item on all homework is YOUR NAME!
No name, no credit. ALSO, put last 4 digits of SS#.
Staple or clip pages together.
Homework must be submitted when due. You loose 10%, one grade, the first day homework is late. Then 10% each week thereafter. Max 50% off. A zero really hurts your average! Paper or EMail to squire@cs.umbc.edu is acceptable. If I can not read or understand your homework, you do not get credit. Type or print if your handwriting is bad. Homework is always due on a scheduled class day within 15 minutes after the start of the class. If class is canceled then homework is due the next time the class meets.
EMail only plain text! No word processor formats.
You may use a word processor or other software tools and
print the results and turn in paper.
Put CS411 and HW number in subject line.
The "submit" facility only works on the "irix.gl" machines.
The student commands are:
submit cs411 HW4 file puts your "file" into cs411 HW4
submitrm cs411 HW4 file removes your "file" from cs411 HW4
submitls cs411 HW4 lists your files in cs411 HW4
Note: For this semester the 'HW4' can be HW4, HW6, part1, part2 or part3.
a) you must have your userid registered for "submit"
send mail from a gl machine to squire if your submit fails
b) you have to be logged onto a gl machine, kermit or telnet are OK
c) everything is case sensitive, sorry about the uppercase HW.
Book Page 45, Exercises 1.1 through 1.26.
The answer is just two columns. The first column is the numbers
1 through 26, the second column is the answer letter from the set {a-z}
You do not have to copy the questions, but show the
computation and clearly indicate the answers..
Be sure to label the answers with the Exercise number.
Book Page 93, Exercises 2.18, 2.19, 2.20
Book Page 101, Exercises 2.41, 2.42
Using the program matmul2.c from here or Downloadable source:
On a GL SGI machine, MIPS architecture only:
Part 1. Compare the assembly language printed by two compilers.
Part 2. Compare the assembly language printed by the compiler vs
the instructions in memory at execution time.
Note: The answers are not unique. It depends on which
compiler is used, which specific machine is used and
which options are used.
This assignment must be run on a GL SGI machine using:
c89 -g3 -O3 SGI compiler
gcc -g3 -O3 gnu compiler (much different on MIPS architecture)
^_____ letter upper case oh, NOT zero !
--------------------------------------------------------------------
Part 1
for getting assembly language source code to a file matmul1.s
gcc -g3 -O3 -S matmul2.c
mv matmul2.s matmul2gcc.s (save, next clobbers.)
c89 -g3 -O3 -S matmul2.c may create matmul2.s
mv matmul2.s matmul2sgi.s
Now, look in the files matmul2gcc.s and matmul2sgi.s
Ignore all lines where the first character is a dot "."
a) How may mul.d instructions in matmul2gcc.s ?
b) About how many mul.d instructions in matmul2sgi.s ?
c) Why is there a big difference (e.g. what compiler optimization) ?
------------------------------------------------------------------
Part 2
When running with redirection, ">", first test without redirection
to be sure you can type the correct input and it works. Then
type carefully or use a script to make the redirected run.
Extra "enter" keys may be needed at various places.
Ignore warning messages from debugger.
Remember memory addresses are in bytes, instructions take 4 bytes.
(Even in the 64 bit machine!)
In assy.out use main:nn number to relate to hex.out to find the same word.
In the following sequences of commands, blank lines are typed as "enter"
gcc -O3 -S matmul2.c # strip comments from matmul2.s
gcc -g3 -O3 matmul2.c # need debug for "stop main" to work
dbx -d a.out > hex.out
stop main
rerun
list 1,26
(#1)/100X
q
dbx -d a.out > assy.out
stop main
rerun
list 1,26
(#1)/100i
q
Capture to a file with redirection or commands like:
record output file-name.out
unrecord
The instruction field format is on page 117 of textbook, also 121, 131 or
appendix A-73 area.
mul.d is the MIPS=SGI double precision floating point multiply, "R" format.
Watch out for where the register values are placed.
(R2000 instructions differ from UMBC8 or UMBC9 that are R?000.)
Most of the instruction in the loop are "housekeeping", there are various
instructions for loading and storing data, l.d and s.d are just one pair.
a) Do the instructions have the same names in matmul2.s and assy.out ?
b) What does #nop in matmul2.s get converted to in assy.out ?
Is it the same every time ?
c) Find the mul.d instruction in assy.out
Write the assembly language line.
Look up that instruction in hex.out
d) Write the mul.d as hexadecimal (from hex.out) and
e) Write the mul.d as six integers for the fields 6,5,5,5,5,6 bits
"submit" a single file named add32c.e that is a fast carry 32 bit adder.
(This is not the same adder as previous classes)
You will use this file in HW6 and the three parts of the project.
It is not important what the signal names are in add32c.e,
but keep the same size and order.
Build a four bit fast adder component or download add4c.e
You need a 32 bit adder, so use eight add4c components in
an add32 component [NO 'c' on component name] , cin goes into bottom
stage, the carry out of each stage goes into the bottom of the next stage,
the carry out from the last stage gets the signal name cout.
Use unique signal names or unique subscripts. All connections with
the same name are tied together and have the same value.
Build a main circuit for testing your add32 component or download tadd32c.e
Get the .run file to test your circuit tadd32c.run
Use these commands to set up esim and ecomp, then compile and simulate:
On irix.gl.umbc.edu
ln -s /afs/umbc.edu/users/s/q/squire/pub/ecomp ecomp
ln -s /afs/umbc.edu/users/s/q/squire/pub/esim esim
(remember to rm esim rm ecomp if typed wrong first time.)
or on linux.gl.umbc.edu or UMBC PC booting Linux
ln -s /afs/umbc.edu/users/s/q/squire/pub/linux/redhat52/ecomp ecomp
ln -s /afs/umbc.edu/users/s/q/squire/pub/linux/redhat52/esim esim
ecomp add32c.e tadd32c.e -o tadd32c.net
esim < tadd32c.run > tadd32c.out
Check to file tadd32c.out to be sure your adder worked.
The answers are in tadd32c.chk
You can check your output with the command diff tadd32c.out tadd32c.chk.
Submit ONE file add32c.e that has the component add32 in it.
submit cs411 HW4 add32c.e
Your circuits must run. Incorrect results loose points.
Late submittals loose even more points.
You must include a few comments so anyone reading your circuits can
understand them.
Follow the links below to Project and Download for more information.
See the writeups on ecomp, esim, tutorial and sample circuits.
The building blocks become part of your final project.
1. Write two esim statements that implement the truth table below
Just use and "&" or "|" and not "~" with parenthesis.
the answer starts x <=
y <=
a b c | x y
------+----
0 0 0 | 0 0
0 0 1 | 0 0
0 1 0 | 1 1
0 1 1 | 1 0
1 0 0 | 0 0
1 0 1 | 1 0
1 1 0 | 0 0
1 1 1 | 0 1
2. Write the esim statement that implements the logic diagram
+----+
a --|OR |____
b --| | |
+----+ | +----+
--|XOR |
+----+ | |
c --|AND |_____| |__
d --| | | | |
+----+ | | |
--| | |
+----+ | | | |
e --|NOT |---| +----+ | +----+
+----+ |--|AND |
| |-- g
f ------------------------| |
+----+
3. Draw the logic diagram that represents the esim statement
g <= ((~a|b)^(~c&d&~e))|(~e&f);
4. textbook, Page 330, Problem 4.49 with the additional instructions:
Use A, B, E and F all as four ones. e.g. A <= #b1111 etc.
The answer is a six bit result S.
5. textbook, page 331, Problem 4.50
Watch out, the problem states 2T, not 1T
Be sure to count the longest path.
Code a circuit using one 32 bit adder that performs a serial multiply
followed by a serial divide. Use 32 bit numbers with the sign bit set
to zero. You do not have to correct the remainder after division.
You may use one or more counters, as many multiplexers
and assorted gates, signals, clocks as you need. But, only one
32 bit adder.
You may use the sample esim code from the download directory, printed
copy handed out and discussed in class, for the multiplier
mul_ser.e and for the divider div_ser.e
Set up your circuit to perform the multiplication of 31 times 85 with
the resulting 64 bit product in the "hi" "lo" registers. This should
take 32 clocks. Then you circuit divides the "hi" "lo" registers
by 15 with the quotient in the "lo" register and the remainder in
the "hi" register. This should take an additional 32 clocks.
DO NOT implement the Booth multiply, do use the non-restoring
divide algorithm.
Have everything needed for the simulation in one file named
mul_div_ser.e (This includes your complete 32 bit adder,
counter(s) and test driver circuit.
Code up a file mul_div_ser.run that is similar to div_ser.run
that was handed out and can be copied to your directory.
Produce labeled print out, using "puts" statements for at least
the "hi" "lo" and clock counter, "cntr"
Check that at the end of the multiply, "hi" and "lo" have
the value 31 times 85. (The counter may read 31 or zero or
32 if you used a 6 bit counter.)
Check that at the end of divide, "hi" has the remainder of
(31 * 85) / 15 and "lo" has the quotient of (31 * 85) / 15.
The counter value is not important, but stop the simulation
using the control available in the .run file when the result
is correct in "hi" and "lo."
When the check is OK, submit cs411 HW6 mul_div_ser.e
submit cs411 HW6 mul_div_ser.run
Closed book. Multiple choice questions based on reading assignments
and esim lectures and homework.
Exam covers book: 1.1-1.6 common sense questions, not dates or people
2.1-2.6
page 118, 146 and 148 instruction formats
4.1-4.8
Exam covers homework: HW1-HW5
Exam covers esim tutorial.
Last updated 10/10/00