AT89S52 - 4 displays, keyboard matrix and PROGRAM

Hey Guys!

I have a project to do, but I have no idea how to do it ...

I have something like this:

and for that I have to connect the keyboard matrix (0 - 9).

The program is operated as follows:

The first and second button to select the display (the display is selected to have a blinking dot)
The third button switch on / switch off the keypad to enter numbers (display is not active = dot off)
The fourth button - turn on / turn off features subtracting 1 every half second of all numbers.
Additionally, during the subtraction (4th button) on port P2 LEDs are lit on and off (hose down)

P0.0 - P0.7 a - h
P1.0 - Display 1
P1.1 - Display 0
P1.2 - Display 3
P1.3 - Display 2
P1.4 - Button B
P1.5 - Button A
P1.6 - Button C
P1.7 - Button D
P2.0 - P2.7 - LED's 0-7
P3.0 - P3.7 - Keyboard *

Such a strange order.

* - For setting

I hope for quick help!

Is this an assignment or what? I suggest you start with things one by one. Get your hands on the display first and then move on to the next thing. A schematic will be helpful to find out how displays are connected to controller.
NOTE: We are not going to provide you code we will only provide help to write code. If your code has issues we do help you rewrite your code or even modify it for you

[Topic moved to 8051 Discussion Forum]