Micro-controller to
PC Communication
This project demonstrates communication in between Micro-controller to PC and vise versa.
On
controller board seven push buttons correspond to 6 LED and also with six
virtual bulbs on PC and one for reset to SW off all bulbs. Whenever any push
button pressed corresponding LED and on PC screen bulb glow
By
reset SW all LED and bulb on screen can be SW off at once. One reset button on
PC screen also serves same purpose.
For
proper communication baud rate as 9600 an 11059200 Hz crystal is used. The heart
of the main
Control
board is ATMEL AT89C2051 Micro-controller and its software, Software is written
and debug in BASCOM-51.A free Demo Software BASCOM-51usefull up to 2K bytes
code, can be down loaded from www.mcselec.com
from Holland.
IC of MAXIM Co MAX 232 is used for the communication to Micro-controller to PC. Only 3 wires can be used for communication cable. Six 47 ohms resistors are added to limit the current of LED.
Schematic Diagram of Micro-Controller to PC Communication
Schematic Diagram of Power Supply
A standard regulator L7805 of TO220 casing is used for the controller supply.
a diode is added to protect by reverse supply feeding. Both side of regulator
is filtered by 2200 u F 16 Volts and 220 u F 10 V capacitors. and two nos .01 u F capacitors are added for stability.
Micro-controller Code
Rem AT89C2051 development. Author provides this module as is and
Rem doesn’t guarantee its functionality or suitability for any
Rem particular purpose
Rem Pl. E-Mail any question and suggestion to syedpervez@yahoo.com
Rem **** Micro-Controller to PC Communication. ****
Rem **** Update on 25-10-2005 ****
Rem Controller send a string of 6 bytes
Rem with added characters ";" in the start
Rem and "ok" at the end, pc receive this string
Rem and sort-out the information of on-off Bulbs
Rem in vb program.
Rem Reset command is transparent for both pc or
Rem controller to switch off all LED simultaneously.
Rem sw status information stays in a array of 6 bytes
Rem and updated whenever a SW is pressed.
$regfile = "89c2051.dat"
$romstart = &H0 ' code starting address
$crystal = 11059200 ' CPU 11.0592 for 9600 baud
$baud = 9600
$timeout
Dim Num As Byte
Dim Count As Byte
Dim My_data(6) As Byte 'declare arrays of 6 byte
Gosub Clear 'initially clear all arrays
Do
Debounce P3.2 , 0 , Clear , Sub 'clear all arrays
Debounce P3.3 , 0 , Ar1 , Sub 'place "1" if pressed
Debounce P3.4 , 0 , Ar2 , Sub '-----do-----
Debounce P3.5 , 0 , Ar3 , Sub
Debounce P3.7 , 0 , Ar4 , Sub '-----do-----
Debounce P1.0 , 0 , Ar5 , Sub
Debounce P1.1 , 0 , Ar6 , Sub '----do-------
Print ";"; 'indicate the start of information
For Num = 1 To 6
Printhex My_data(num); 'just transfer whatever array have
Waitms 5
Next
Print "ok" 'shows the end of string
Input My_data(7) Timeout = 1000
If My_data(7) = 1 Then Gosub Clear
'Waitms 10
Loop
Ar1:
My_data(1) = 1 'place "1" in the corresponding array
Reset P1.7 ' which ever PB. switch is pressed
Return
Ar2:
My_data(2) = 1
Reset P1.6
Return
Ar3:
My_data(3) = 1
Reset P1.5
Return
Ar4:
My_data(4) = 1
Reset P1.4
Return
Ar5:
My_data(5) = 1
Reset P1.3
Return
Ar6:
My_data(6) = 1
Reset P1.2
Return
Clear:
For Count = 1 To 6
My_data(count) = 0 'clear all arrays by placing zero
Next
Set P1.2
Set P1.3
Set P1.4
Set P1.5
Set P1.6
Set P1.7
Return
End
Download all the files, document PDF , Capture ORCAD schematic Diagram, Micro-Controller Code basic and hex file in one ZIP File DOWN LOAD
Basic Compiler BASCOM-51 can be download by their web site http://www.mcselec.com.
and AT89C2051 Data sheet can be download by ATMEL web site http://www.atmel.com
