# Principles of Computer Organization

Discussion in 'OT Technology' started by mrburner, Oct 21, 2003.

1. ### mrburnerRon Paul 2008

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this class is killing me...here the few homework questions that we have due on wednesday that i was unable to do

i'm not asking for anyone to do these for me...but if anyone can lead me in the right direction on any of these, it would be appreciated (4 total)

1. A room has three doors (door A, door B, and door C). Each door has a light switch that can turn the room light off or on. Flipping any switch will change the condition of the light. Assume the light is off when all of the switches are off. Design a circuit to implement this function.

2. Develop a circuit for a controllable logic unit (CLU). This CLU will process two single-bit values according to a set of control inputs. Functions to be performed are AND, ORD, NOR, and NAND.

3. Design a burlar alarm system. The system will have three sensors and an activate feature. The first sensor D will detect door open 0 or door closed 1. The second sensor M will detect motion. For no motion this sensor will give a 0. The last sensor W will detect window opening. A value of 1 from this sensor indicates the window in closed. The activate feature F will disable the alarm when its value is 0. The alarm system will have a single output A. When A=0 the alarm is not sounded. The alarm will sound if there is motion, if te window is open, or if the door is open. A disabled alarm will not sound. Design a circuit to implement this function.

4. Design a garage door controller (GDC). The GDC will have two inputs. The first is called change C. If the door is up, C will cause it to go down. If the door is down, C will cause it to go up. The second input is lock L. Lock will have no effect in its inactive condition. An active lock signal causes the door to go down if it is up or stay down (ignore C) if it was down. Outputs from the GDC will be an up signal and a down signal.

any help on any of the problems would be much appreciated...thanks in advance

2. ### Zourn16-bit NinjaOT Supporter

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on number one, if switch_off=0 and switch_on=1, then
If S1+S2+S3=Even #, Then Light=off
If S1+S2+S3=Odd #, Then Light=on

Prolly doesn't help much,

3. ### sammNext in Line

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number 2 is a simple 1 bit ALU

Use a 4to1 mux to select the output.

4. ### mrburnerRon Paul 2008

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samm...can you explain in a little more detail

and bump

5. ### MPNew Member

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this sounds really familiar. WHere have i heard those questions before... hmmm

6. ### mrburnerRon Paul 2008

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can you help if it sounds familiar?

7. ### sammNext in Line

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you have two inputs: a and b
they're both 1 bit in width

There's a 2 bit wide input as well, this is the select signal to the MUX to determine which output to use.

The logic for AND, OR, NAND, and NOR should be self explanitory. Just input those into the MUX and you're set. It's a basic 1 bit ALU. Shouldn't your textbook cover this stuff? Any of the Patterson & Hennessy books would have it.

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