Input Output Sharing Same Port

Status
Not open for further replies.
H

Help

Advanced Member level 2
Joined
Feb 15, 2005
Messages
617
Helped
7
Reputation
14
Reaction score
3
Trophy points
1,298
Activity points
7,065
Hi,

I'm using uC controlling the multiplexer. P1^0...P1^2 is control addressing multiplexer and the P1^7 is get the result from multiplexer.

Is it possible to do that? How am i to write the code?

Please advice.

Thank You.
 

AA,
Yes you can do this.
here are the codes the code
; making P1.0 ... P1.2 work as an input
SETB P1.0;
SETB P1.1;
SETB P1.2;

;Writing to these bits:
MOV A, #value
MOV P1, A

;Reading from P1.7
MOV C, P1.7

BR,
Amr Ali.
 

Hi,

I'm not so familiar with assembly language. :|

I had slightly your an assemble to C.
Code: 
sbit PB0 = P1^0;
sbit PB1 = P1^1;
sbit PB2 = P1^2;

sbit PB7 = P1^7;

void main()
{
	bit rst;

 	while(1)
	{
		PB0 = 1;
		PB1 = 0;
		PB2 = 1;

		rst = PB7;
	}
}
Do you mean that?

Actually i wish to structure the port IO. ex. P1^0...P1^3 is output and P1^4...P1^7 is input.
Perhap using Bit Field mothed.
Code: 
struct IO{ 
     unsigned char OLSB:4;   // P1^0...P1^3
     unsigned char IMSB:4; // P1^4...P1^7
}
My idea is like this.
Once i assign the OLSB=3; the output port for P1^0...P1^3 result will be 1100.
So for the IMSB is ready to read the data from the port.

Code: 
OLSB=3;     // control output bit 
rst = IMSB; // receive result from the port.

Is it possible to do that?

Thank You.
 

in 8051 u can take input and output from any pin

Remember for Inputs u have set those pins
 

ashad said:
in 8051 u can take input and output from any pin

Remember for Inputs u have set those pins
Click to expand...
Thank for your remind. I understand about it.
How am i to do that? Please advice.

Thank You.
 

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…