‫Welcomed the Alieu demonstration but the base is too short for this demonstration.
‫We have two four digit seven segment displays located on solderless breadboard where each of the segments
‫are tied together through a 56 ohm resistor that is fed into the J and J b p mod ports of the Base to
‫board.
‫We also have all the digits selects all eight of them are connected through a two and thirty nine or
‫four and transistor where the 470 ohm resistor are connected through the base and these are fed and
‫controlled through the J.C. Jaydee the main ports of the bases to board we also are using switches 7
‫6 and 5 for the opcode of the Alieu we have are using switch one to determine if we're going to add
‫or subtract whenever we want to select the value we're going to place into that A and B and R switch
‫0 selects which which value we're displaying for displaying value or displaying value B and Button 0
‫determines if we're going to add or subtract one button to button one is ours check ten button to add
‫or subtract 100.
‫Button 3 is the exit queue.
‫So that will start the Alieu and execute the command.
‫So to start off we are displaying our switch 0 is pulled down or displaying the FI pull switch up.
‫Display.
‫Now both are set to zero and we are initialized so that is why we don't see a difference when we switch
‫from down to up.
‫So right now we're just playing a and or add subtract is down.
‫So we're going to subtract.
‫Let's pull that up and we'll press button 0.
‫You can see we're adding one.
‫If I pull it down the switch too and I hit that we subtraction our down to zero.
‫I hit it once again.
‫We go down to a negative one into the negative as indicated by the the far left segments I want to see
‫why having the centerpiece illuminated so we can go ahead and select the value for a will make it negative
‫3 and we can go up by 10 or by 100.
‫And if we just add we can go right back to where negative 3.
‫So we're at negative 3 on our input A.
‫If we select down our input B is still 0.
‫So our input B is now displayed on the 7 segment display.
‫And just like before we can add if we have our add subtracts which called high if we pull low now we'll
‫subtract and we can go down the negatives.
‫But we're going to make our be a positive number so we'll make that a positive too or we'll make it
‫a positive for.
‫So our input A is a negative three and B is a positive for.
‫So right now let's run through the different opcode operations to see how how this works.
‫So the first opcode operation we have is three zeroes.
‫So we pool our switch 7 switch 6 and switch 5 all down to zero and if we pressed the execute command
‫this will take the value of a and display it in the result register.
‫So to see the value based we poor switch 0 high.
‫So it's a negative 3.
‫So by pressing our execute button we now see we have a negative 3 being displayed in our result register
‫our next command is at 0 0 1 and this will take the value of B which is 0 0 for a place that in the
‫result register for us to execute.
‫Now you see we have a value of 4 in our result register our next command is 0 1 0.
‫So 0 1 0 and this will take the result of a plus b.
‫So we have our negative 3 plus four is a value of 1 to execute and we'll see 1 shows up in the result
‫register.
‫Now for your 0 1 1 that's a minus B.
‫So 0 1 1 that's a negative 3 minus be negative 3 minus 4 is negative 7 which is the value we see displayed
‫in our result register.
‫And now we have two different commands that are used to set all the values to either zero or negative
‫1.
‫So if we set you a 1 0 0 1 0 0 for opcode and press execute this is going to set all of the values in
‫our result register to zero.
‫So basically we're setting a result back to zero execute our result register.
‫We can see is set to zero if we do a 1 0 1.
‫This sets all of the values in a result register to a 1.
‫Now since we're doing a sign notation This is actually the representation of a negative one because
‫in VHDL sign notation is represented using two's complement.
‫And so in twos complement form all ones is the same as a negative one.
‫So we press execute.
‫We'll see a negative one display in our result register and that is the Alieu demonstration running
‫on the basis of or.