Computer Organization Lab 08

CSCI 2500 — Computer Organization
Lab 08 (document version 1.0)
ˆ This lab is due by the end of your lab session on Wednesday, October 23, 2019.
ˆ This lab is to be completed individually. Do not share your code with anyone else.
ˆ You must show your code and your solutions to a TA or mentor to receive credit for each
checkpoint.
ˆ Labs are available by Mondays before your lab sessions. Plan to start each lab early and
ask questions during office hours, in the discussion forum on Submitty, and during your lab
session.
1. Checkpoint 1: For the first (and second) checkpoint, you will use C to finish implementing
a simulation of logical NOT, logical OR, logical AND, and logical XOR.
Download the lab08.c code, which provides fill-in-the-blank skeletal code for these logical
gates, as well as unit test code in main(). Fill in the not_gate(), or_gate(), and_gate(),
and xor_gate() functions. Verify that the truth table outputs are correct.
2. Checkpoint 2: For the second checkpoint, continue to add to the lab08.c code by implementing the multiplexer(), decoder(), and alu_1bit() functions. Make sure that whenever possible you reuse functions that you already implemented. Also add code to main() to
comprehensively test your decoder() and alu_1bit() functions. As above, verify that the
truth table outputs are correct.
Then, implement the alu_4bit() function reusing alu_1bit() function. Verify the correctness of your implementation of alu_4bit() by comparing the results with the “expected”
values.
3. Checkpoint 3: For the third checkpoint, write a function called ieee754encode() that
has the function prototype shown below and generates the encoding of a single-precision
floating-point value in its 32-bit binary form.
void ieee754encode( float value, char * encoded );
This function accepts two arguments. The value argument is the actual single-precision
floating-point value to be encoded (e.g., 57.75). The encoded argument points to where the
normalized binary string should be stored, with the binary string representing the IEEE 754-
1985 form (e.g., "01000010011001110000000000000000").
You can assume that the encoded argument points to a valid chunk of memory of at least 33
bytes. And as a character string, you will need to generate the correct series of '0' and '1'
characters. Be sure to use the normalized form.
Your function should output the following debugging information:
input: 57.750000
sign: 0
exponent: 10000100
fraction: 11001110000000000000000
output: 01000010011001110000000000000000