Using AD9 to draw the minimum system __PCB of the 51 monolithic microcomputer

First step: Install AD9 software

Step Two: Open AD9, New project

The third step: continue to create new schematics and PCB files, new files will be saved to the newly-built project

NEW schematic:

New PCB File:

When you're done, you'll be on the left side of your screen:

Fourth step: Save the project

As shown above, right click on the project name, choose Save PROJRCT as this option, will jump out the following dialog box

Note that at this point the file suffix is named. PRJPCB said that the preservation of the PCB project

After the preservation of the PCB project, will automatically let you save the schematics and PCB files, their suffix name is respectively. Schdoc and Pcbdoc.

Fifth Step: Add components

In AD9, all the components are placed in the library, so to place the components first to add a library file

Also is the right key project name, select Add Existing to project, add the existing library into the project, it should be noted that the library file must be placed in the same directory as the project file

You can see the information of all the components in this library in this window of Sch.

After the library has been added, you can start placing components, open the Library window in the schematic file, find the libraries you added, and find the components you need.

Sixth step: Draw the main control circuit

The smallest system of single chip microcomputer consists of three parts: Crystal oscillator circuit, reset circuit and main control circuit.

Let's start by drawing the main control circuit:

Select the desired at89c51 chip, press the place at89c51 button in the upper right corner, and you will find that the component is attached to the mouse and the mouse becomes the shape of the cross.

After placing the chip, the network marking of the grounding of the power supply is placed on the pin of VCC and GND

If you think VCC and GND placed too close to the pin, here's a little trick, hold down the CTRL key and then drag the components, the components will be connected to the line drag, you do not have to place the line, the other components are the same

So the main control circuit is complete.

Seventh Step: Draw the Reset circuit

Reset circuit in the smallest system is essential, whenever the power is connected, we hope that the microcontroller can restart the work, this time need to reset the circuit

Also pull out the components from the library, connect the components with the wire, and end up with the chip's RST pin.

Here are two ways:

① directly with the line to connect the Reset Circuit unit to the RST PIN

② method of using network marking

In the minimum system schematic diagram, both methods can be, but if it is a more complex circuit diagram, we are more inclined to adopt the network marking method, can make the schematic diagram clearer

Can modify the name of the network label, here we use RST

The drawing good reset circuit is such, 51 monolithic integrated circuits uses is the high electricity to be pacified the position, the SW1 function is May the manual control reset

Eighth step: Painting crystal oscillator circuit

The crystal oscillator circuit to the single chip computer function is equal to the heart to the human function, 51 single-chip computer's working frequency is 12MHz

Using the above operation, will soon be able to draw the crystal oscillator circuit

Nineth Step: layout of schematic diagram

So the smallest system of a single chip is complete.