getting help with 89v51rd2 serial port data

[dongdurex]

I'm trying to receive data from PC via serial port.
But so far I can't get the data in array of chars (char[]).
Here is the program I've from my department.

#include <p89v51rd2.h> // Header file register for P89V51RD2FN
unsigned char Get_Serial(void)
{
	bit Timeout=0;
	unsigned char count=252, Data = 0;
	while((Timeout == 0))
	{
		if(RI == 0)
		count++; //waiting
		else
		{
			Data = SBUF;
			RI=0;
			return(Data);
		}
		if(count <= 2)
		{
			Timeout = 1; //Timeout!!
		}
	}
	return(Data);
}

void Send_Serial(unsigned char x)
{
	TI = 0;
	SBUF = x;
	while(TI==0);
}

void Serial_initial()
{
	TMOD = 0x21;
	SCON = 0x50;
	TH1 =0xFD;
	TL1 =0xFD;
	TF1 = 0;
	TR1 = 1;
	TI = 0;
}
void main(void) // Main loop
{
	unsigned char Data=0; // ******** I'm thinking that the data gets in from this line
	Serial_initial();
	P1 = 0x80;
	while(1) // Infinite loop
	{
         //My main loop which I need to apply a string like data.
        }
}

If I send a data from PC as "10"
The program will only read '1'
which is not correct.

please give me some advice.
ps. sorry for my English, it's not my primary language.

 

[srikanthsamaga]

The Get_Serial function can recieve only one bit at a time.
In your main function, you need to collect each byte and store it in a array

ex: to recive "10", you nedd to call Get_Serial two times.

 

[dongdurex]

By any chance I can change my code to something else.
Because this method is troublesome, I have been stuck with it for a very long time now.

Can I change it to get the data by something like scanf or something else.

 

[Ian Rogers]

Unfortunately No!! scanf() would be nice.

I haven't got C code to utilize a circular buffer and use an ISR to do the job
If you can covert this to C (should be easy)

; THIS CODE IS WRITTEN BY " MUBASHAR YASIN " (ELECTRICAL ENGINEER)
; ISLAMABAD,PAKISTAN, CELL# (+92)0301-8557978 ,mubasharpk09@yahoo.com
; please visit--> www.geocities.com/kool_projects
;----------------------------------------------------------------------------
;THIS PROGRAM IMPLEMENTS A CYCLIC BUFFER ON THE SERIAL PORT(RECEIVED DATA)
;MEMORY POINTERS ARE STORED IN THE REGISTERS R0&R1(STARTING ADDRESS IS 20H)
;BUFFER LENGTH IS 20H TO 30H LOCATION
;BUFFER SIZE CAN BE VARIED ACCORDING TO YOUR REQUIREMENT AND SIZE OF RAM
;----------------------------------------------------------------------------	
	
	START EQU 20H

	ORG 0000H
	LJMP MAIN

	ORG 0023H
        LJMP SERIAL_ISR
	
;;;;;;;;;;;;;;;;
SERIAL_INIT:
;;;;;;;;;;;;;;;;
        MOV SCON,#52H ;8-BIT UART,REN
        MOV TMOD,#20H ;8-BIT AUTO RELOAD MODE
        MOV TH1,#-3   ;9600 BPS AUTO RELOAD VALUE
        SETB EA       ;GLOBAL INTERRUPT ENABLE
        SETB ES       ;SERIAL INTERRUPT ENABLE
        SETB PS       ;HIGH PRIORITY FOR SERIAL INTERRUPTS
        SETB TR1      ;START TIMER
        RET
;;;;;;;;;;;;;;;;
SERIAL_ISR:
;;;;;;;;;;;;;;;;
	PUSH ACC
	JNB RI,TMT
	CLR RI
	MOV A,SBUF
	LCALL WRITE_BUF
	LJMP EXIT1
TMT:    CLR TI
EXIT1:	POP ACC
	RETI
;;;;;;;;;;;;;;;;
WRITE_BUF:
;;;;;;;;;;;;;;;;
	CJNE R0,#31H,NEXT1  ;CHECK FOR BUFFER RECYCLE 
	MOV R0,#20H         ;CYCLE AGAIN
NEXT1:	MOV @R0,A
	INC R0
	RET
;;;;;;;;;;;;;;;;
SERIAL_READ:
;;;;;;;;;;;;;;;;
	MOV A,R0
	MOV B,R1
	CJNE A,B,NEXT2       ;COMPARE R0 & R1
	LJMP EXIT2	     ;NOTHING TO READ(BUFFER EMPTY)
NEXT2:	CJNE R1,#31H,NEXT3
        MOV R1,#20H          ;JUMP TO START (RECYCLE)
NEXT3:	MOV A,@R1
        INC R1
	LCALL DELAY
	LCALL SERIAL_OUT     ;BOUNCE BACK
EXIT2:	RET
;;;;;;;;;;;;;;;;
SERIAL_OUT:
;;;;;;;;;;;;;;;;
	MOV SBUF,A
	RET
;;;;;;;;;;;;;;;;
DELAY:
;;;;;;;;;;;;;;;;
	MOV R3,#250
RPT:	NOP
	NOP
	DJNZ R3,RPT
	RET
;;;;;;;;;;;;;;;;
MAIN:
;;;;;;;;;;;;;;;;
	MOV R0,#START        ; 'WRITE' POINTER
	MOV R1,#START        ; 'READ' POINTER
	LCALL SERIAL_INIT
AGAIN:	LCALL SERIAL_READ
	LJMP AGAIN
	END

This is from 8052.com.

 

[gagandeep]

i am using philips P89v51rd2 Uc kit in lab.
whenever i burn my program for LCD it works without DEALY only
Is there a problem in kit??

 

[Ian Rogers]

Works without delay's but doesn't work with delay's? There is a problem with the code...

Check the link in my signature ( last one) My tutorials have quite a bit of what you are trying to achieve... there are LCD routines you can port... there are also RX / TX routines.

 

[gagandeep]

i am programming in Assembly language... code is correct.... simply displaying name on lcd... single alphabet is displaying