This document describes a temperature control system using an 8086 microprocessor. It includes a block diagram of the components, including an 8279 interfacing with the 8086 microprocessor. It also includes flowcharts and descriptions of the program modules, including an executive section in Module 1 that initializes components and stores temperature and timing variables. Module 2 contains interrupt service procedures, Module 3 contains loop service procedures like temperature control, and Module 4 includes utility procedures like LED display and A/D conversion. The goal is to use this system to maintain the required temperature in industrial processes by controlling heaters based on feedback from temperature sensors.

1. BY
VIKAS ARYA
M.TECH (FULL TIME)
“TEMPRATURE CONTROL USING 8086
MICROPROCESSOR”

2. INTRODUCTION
 In most of the manufacturing industries like chemical,
petrochemical, food processing, pharmaceutical and some
time in scientific research etc temperature is one of the main
parameter to be control. Because in these kind of industries
some product need the required temperature to be
maintained at highest priority otherwise the product will fail .
So the temperature controller is most widely used in almost
all the industries.

3. BLOCK DIAGRAM

4. 8279 INTERFACING WITH 8086 MICROPROCESSOR

6. TEMPERATURE VERSUS TIME RESPONSES FOR THERMOSTAT –CONTROLLED AND MICROCOMPUTER
CONTROLLED HEATERS

7. FLOWCHART

8. PROGRAM
 1. Module 1 mainline
 2. Module 2 interrupt service procedures
 3. Module 3 loop service procedures
 4. Module 4 utility procedures

9. 1. MODULE 1 MAINLINE OR EXECUTIVE SECTION
USES PORT P2B (FFFAH) AS OUTPUT
USES PORT P2A (FFF8H) AS DATA INPUT
USES PORT C (FFFCH) AS END OF CONVERSION
INITIALIZE 8259
INITIALIZE 8254 COUNTER 0 TO 1 KHZ OUTPUT
COUNTER for number of interrupts
TIME HI HEATER RELAY TIME ON
TIME LO HEATER RALAY TIME OFF
CURRENT TEMPRATURE
SETPOINT
TEAMPRATURE STORAGE FOR LOOP COUNTER
.

10. 2. MODULE 2 INTERRUPT SERVICE PROCEDURES
 Interrupt procedure to service keyboard
 Interrupt procedure to service process control loop

11. 3. MODULE 3 LOOP SERVICE PROCEDURES
Contain the procedures to service loop
Procedure to service temperature controller

12. 4 . MODULE 4 UTILITY PROCEDURES
 Procedure to display data on 8086 leds
 Procedure to control A/D converter
 Converts an 8-bit binary number to packed BCD equivalent