Lab1 Lab2 wiki (en)

Data sheet

7400-series

 7400.pdf   7402.pdf    7408.pdf    7432.pdf  
 7474.pdf    7486.pdf    74175.pdf    74283.pdf  

Breadboard-simulator

  JavaBreadboardSimulator.pdf

 JBBsim.zip     ( we have changed the images to the european symbols )

Java Bread Board Official Site

A good tool to make preparation tasks, and to simulate the circuits before the labs, is Java Breadboard Simulator. You download the simulator as a ZIP file from the course web. In school, you unpack the ZIP file in your server folder under  H:/,  eg.  H:/JBBsim  ( or at home. In  C:/JBBsim ),  and start the simulator, by double-clicking  the batch file  go.bat  who are among the unziped files.

If you want to avoid "computer problems"? The school's computer lab, with Windows PCs are suitable for use in this course. JBB-works there.

At home you first see to have Java on your computer, before you pack up your files (anywhere). JAVA can be run with most operating systems and some different appropriate command files to start the simulator is supplied.

  ( If necessary, download the Oracle JVM )

It seems that JBB is unable to run the java version 8, in that case, use Version 7 Update 7.1.

JBBuserGuide

Inside a breadboard there are contact groups that cover five vertical holes.
The upper horizontal contact group is for + 6V power supply,
and the lower contact is for ground (voltage source minus).

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The logic gate truth tables
(Before the lab Combinatorial circuits)

NAND-grind 7400

Start with the menu item  Insert Breadboard  to get a breadboard to work with. You can download several breadboard after another if one breadboard would not be enough.

Then you obtain components. Download once with   Insert - DIP Switches - Double   and twice with   Insert - LED - Green   and once with   Insert - LED - Red.  The components end up in the wrong spot on the breadboard, but you can click and hold down and drag them right. Here we have used a convention to show input signals with green LEDs and output signals with red.

The circuit 7400 is retrieved with the command   Chip - TTL - logic - Gen7400 - OK,  and dragged with the mouse to the right place.

Red wire color is selected with command   Wire - Red,  as well as other colors. To begin to draw lines selected command   Wire - Add Wires.  At the starting point, left-click it, at the end point, double click. If you need to pull the lead angle, click on every bend. The upper row of holes is the supply voltage + 5V ("1"), and the lower is ground, 0V ("0"). We have used the convention to connect the supply voltage with red lines, and ground with black. Other wire colors are chosen so that the connections are clear.

  

During the lab, you only have access to the DIP switches and LEDs. We then uses components that have the same characteristics as in this simulator. (The LEDs at the lab has Built-series resistance).
ATTENTION! The simulator can only simulate digital signals. Special couplings that give rise to intermediate voltage values will therefore not be simulated correctly. (eg. series-connected LEDs).
Making the connections as in the figure above, one can be sure that the simulations will be consistent with reality at lab.

Even "virtual" components

The simulator also has components that do not correspond to reality, for example a simulated Hex Display that can be retrieved with the menu item   Insert - Chip - Components - Hex Display.   The advantage of the display is that it is simpler to interpret than just LEDs, even when, as here uses only the digits 0 ... 3.

The simulator has   stop-pause-stepped-buttons   that use generally accepted symbols (similar to those on a cassette recorder).

  Start the simulation, and then click the component  Double Dip Switches  to change the setting on/off so that you thus go through the four input combinations. Fill out the truth table.

A still more convenient test circuit can be obtained by replacing the Double Dip Switches to  HexKeyPad  (menu command   Insert - Chip - Components - HexKeyPad).  If you then double-click on this simulated "component" it opens a keyboard, called a KeyPad. With this KeyPad you can comfortably enter the hexadecimal numbers 0 ... F. We use the numbers 0 ... 3.  Please note! The lines in orange shows that even some of the yellow wires need to be changed for this connection.

 

They virtual components  HexKeyPad  and   Hex Display  are comfortable to use - but to prepare and document the actual lab connection it is the  Dip Switches  and  LED  that are applicable.

AND-gate 7408

Highlight 7400 circuit and remove it with the delete key.    ( first stop the  simulation ).

Download the circuit  Gen7408  with the command   Chip - TTL - logic - Gen7408 - OK.  Repeat the simulation with this component and fill in the truth table.

  

OR-gate 7432

Repeat the same for the OR gate 7432.

  

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Combinatorial circuit
(Before the lab Combinatorial circuits)

All connections you make with the combinational circuit at the lab, you can simulate in advance at home.

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Addition of 8-bit numbers or 4-bit number
(Before the lab Combinatorial circuits)

At the lab, we have the chip 74283 which is a 4-bit adder. The circuit is not included with the simulator, instead there is a "fantasy circuit" - an 8-bit adder.

One must therefore choose between to "choke down" the circuit to 4 bits, as shown in the figure below, or simulate the addition of 8-bit numbers.
If A3 and B3 are both "1" the full adder stage  A4 and  B4 recieves input carry "1" regardless of what values the previous inputs (CIN A0 B0 A1 B1 A2 B2) has had (they can be left unconnected)! A3 and B3 can then be connected together as input-carry CIN  to a "four bit adder" with inputs A7 A6 A5 A4 B7 B6 B5 B4 and the sum S7 S6 S5 S4.

8-bit adder is found under the Insert menu - Chip, then double click on  - cpu - jx_york_ac_uk - J1 -Adder8bit, and then click OK.

Example of a simulator coupling for 4-bit addition!

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Latch with NOR gates
(Before the lab Sequence Circuits)

  
Examples of simulator coupling to investigate the latch with NOR gates.

ATTENTION!  In the simulation, use 7428 instead of 7402 which has incorrect pin configuration in the simulator!  - Both circuits are in reality the same, only difference is that 7428 is a (stronger) buffer circuit.

Clocked D flip-flop
(before the lab Sequence Circuits)

Hint! The simulator has a special component, a clock pulse generator. The clock pulse generator located under the Insert menu  - Chip, then double click - Oscillator - GenClk, and then click  OK.

D flip-flops are under the Insert menu - Chip, then double click  - TTL - Flip Flops - Gen7474, and then click OK.

Example of a simulator coupling. All the D flip-flop inputs must be connected to the correct logic levels!
Set SimSpeed so that the LEDs flash at approximately sec speed.
Appropriate speed setting depends on your computer's performance.

Gray code up/down counter
(Before the lab Sequence Circuits)

Unfinished simulator coupling for the the Gray code counter.

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Shift Register Counter
(Before the lab Sequence Circuits)

During simulation, you can use the existing simulator chip 74164, along with an extra XOR gate, as compensation for the missing chip 74175.

The circuit 74175 is not included in the simulator, but some different shift register circuits are included. The thing to do is to use the circuit 74164, which is an 8-bit shift register. Use the last four flip-flops QE QF QG QH. See the figure.

The shift register can be found under the Insert menu   - Chip, then double click - TTL - Shift registers - Gen74164, and then click   OK.

Components needed to simulate the different shift register counters.