8085 Program to simulate a real-time clock

Now let us see a program of Intel 8085 Microprocessor. In this program we will see how to generate real time clock using 8085.

Problem Statement:

Write 8085 Assembly language program to simulate real-time clock.

Discussion:

In this program we are creating a real time clock using 8085MPU. Here we are generating 1s delay to update seconds. This clock is 24Hrs clock. We are initializing the clock from 00:00:00. To display the values into 7-segment display we have to use some Port ICs and correct configurations. In each 60 seconds the minute field is updated, and in each 60 minutes the hour field is updated. For decimal update, DAA instruction is used in each increment.

We are storing the hour field into 8008H and minute field is stored at 8007H. The second value is stored at location 8009H.

Note: Here for simplicity we are storing the numbers into memory. To show the numbers, we can use 7 – segment display and other display function for showing it into the display.

Input:

Here we are not providing any input.

Flow Diagram:

Program:

Output:

The numbers are storing into memory location 8008H – 8007H and 8009H.