Enabling or Disabling a pin in c language for 8051

[rainn]

I am currently making a very simple vending machine project which uses the 8051 microcontoller.
the pins im using is

sbit C=P3^3; ////// “C” is for coffee///////
sbit T=P3^4; ////// “T” is for tea///////
sbit H=P3^5; ////// “H” is for hot///////
sbit D=P3^6; ////// “D” is for cold///////
sbit S=P3^7; ////// “S” is for purchasing/////

i have done the coding for lcd initialization and selection.. the problem now is that i need the program to run in sequence for example

sequence one:
customer should be able to choose only “C” or “T”..
(during this sequence all the other pins should be disabled.. any input will be ignored)

sequence two:
customer should be able to choose only “H” or “D”..

sequence three:
once the above sequence is completed only then customer can press the purchasing push button..

The question is how can i disable the other pins at respective sequences.. my code for the selection part is below.

 

void main ()

{

TMOD=0x02;

TH0=0xA4;

IE=0x00;

L1= L2= 0;

a = 0;

lcd_ini();

delay(20);

lcd_command(0x01);

lcd_string("Select Drink");

delay(200);

lcd_command(0x01);

lcd_string("1.Coffee  2.Tea");

delay(20);

flagset=0;

TR1 = 0;





while (1)

{

if (C==0)

{

delay(30);

lcd_command(0x01);

lcd_string("Coffee: Hot/Cold");

}





if (T==0)

{

delay(30);

lcd_command(0x01);

lcd_string("Tea: Hot/Cold");

}



if (H==0)

{

delay(30);

lcd_command(0x01);

lcd_string("Hot Selected");

}





if (=0)

{

delay(30);

lcd_command(0x01);

lcd_string("Cold Selected");

}



if (S==0)

{

lcd_command(0x01);

lcd_command(0x80);

lcd_string("Processing");

delay(100);

lcd_command(0x01);

lcd_command(0x80);

lcd_string("Please wait");

L1 = 1;

delay(100);

L1 = 0;      ///////L1 and L2 is for lights///////

L2 = 1;

lcd_command(0x01);

lcd_command(0x80);

lcd_string("Remove drink");

delay(100);

L2 = 0;

lcd_command(0x01);

lcd_command(0x85);

lcd_string("Thankyou");

delay (500);





}

}

}

Thank you in advance :-)

[AJISH ALFRED]

Hi,

Is there any statements in the code in which you are reading the input pins?

[rainn]

can i email to u my code??

 

[AJISH ALFRED]

Please post it here. The idea is, others who have the same doubt may find our discussion helpful.

[Author]

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