Assembly Language Assignment:

The key objective of the assignment is to explore knowledge concerning parallel ports of a computer system. You could read and prepare data to/from the parallel port using IN and OUT instructions respectively.

Assume we have designed a device which enables us to control room temperature using a system’s parallel port.

For this circuitry, we have to use:

1. LM35 (Temperature Sensor)

2. ADC8080 (8-bit Analog to Digital convertor)

3. Parallel Port’s data and control blocks.

We have interfaced LM35 (Temperature Sensor) with ADC8080 (Analog to Digital Converter) and Parallel Port of a computer system.

LM35 (temperature sensor) reads room temperature and transmits analog data to ADC 8080 (analog to digital converter), which then converts analog reading (from sensor) to digital data (8-bit binary data). Converted digital data (b-bit binary number) would be read by processor through its parallel port and would control (either increase or decrease) temperature of the air conditioner depending upon working condition/criterion.

Aim:

Students are needed to code the device which controls temperature of a room by signalling an Air Conditioner (AC).

In order to code, you have to consider the following objectives.

1. You have to read room temperature data from parallel port’s data block (8-bit binary data).

2. Check either room temperature is between 21 or 23 degree Celsius (15H and 17H).

3. If Yes, No action taken (program exit).

4. If No, Check either temperature is below 21 degrees or above 23 degrees

a. If less than 21 degrees, increase the temperature by sending a pulse to Air Conditioner Control PIN C0.

b. If greater than 23 degrees, decrease the temperature by sending a pulse to Air Conditioner Control PIN C1.