7 segment display interface to 89C52

seven segment display interface based on 89c52

i want to make small software that count from0-to 99 using at89c52
but i didnt want to use 7447 i want to make a software conter using scan tecniqe
did you got it sir

7 segment interfacing with 89c52

Salam,

I think basic or c language would help u better than assembly

All u have to do is to asign a port for selecting each 7-segment module, another port for sending data (a lookup table can be used to know the data to be sent corresponding to each no)

I think the data is as follows:

0 --> 0x3f
1 --> 0x6
2 --> 0x5b
3 --> 0x4f
4 --> 0x66
5 --> 0x6d
6 --> 0x7d
7 --> 0x7
8 --> 0x7f
9 --> 0x6f

Hope that helps

7 segment display interfacing 89s52

u have to use two ports for interfacing seven segment display with m.controller.In the case of common cathode display,8 pins from port0 is connected to the 7 segments of the c.c display. For a two digit counter two c.c display is used.so the two common cathod pins of the display is connected to the m.controller through a transistor.Collector of bc547(two numbers) is connected to c.c pin Emiter is grounded.base is connected to the m.controller through 10k resister.

Now write down the pattern for display.Ie a low on c.c pin and high on a segment
lightsup the led.A low on c.c pin requires high logic to send to the base of tran
sistor.Now mov the patternn to port0,make c.c pin low,call a small delay of 1ms.
Now mov second pattern to port0 ,make c.c pin low,call a small delay of 1ms,repeat this process
Hope that helps

89c52 display

You have to use Anod common displays if you use at89C52. The microcontroller lines can only sink current. Don't forget to limit the current with 270 ohm resistor (for example) for each segment.

seven segment hex codes

2 ways to do this imo. Use common anode like sugested or use a BCD 7 segment display. The BCD saves portpins and gives you the A-F hex codes for free . If you have enough ports you can connect the displays to separate ports.