Help me about parity bit sourcecode

[Guest]

Please help me "ckielstra" or PCM programmer or anyone can help me.
"ckielstra" !! your source code is not work for me. when i use it by sending data(integer=14) in function it is return 29(integer) to me. Not 0 or 1
why? i'm not well known about asm. (i show my data from lcd)
below is my sourcecode. it's very simple but it's not work.


==============================================
#include <16F876.h>
#fuses HS,NOWDT,NOPROTECT,NOLVP
#use delay(clock=3579545)

#use rs232(STREAM=scard, baud=9600, float_high, xmit=PIN_B0, bits=8, parity=E)
#use rs232(STREAM=scard, baud=9600, float_high, rcv=PIN_B0, bits=9)

#bit ninth_bit = RS232_ERRORS.7

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <input.c>

#define RW PIN_A0
#define RS PIN_A1
#define EN PIN_A2

#define LED0 PIN_A3
#define LED1 PIN_A4

void out_led(int i_led)
{
switch(i_led) // before after
{ // 4 3 4 3
case 0 : { output_high(LED1); output_low(LED0); break; } // 0 0 1 0
case 1 : { output_high(LED1); output_high(LED0); break; } // 0 1 1 1
case 2 : { output_low(LED1); output_low(LED0); break; } // 1 0 0 0
case 3 : { output_low(LED1); output_high(LED0); break; } // 1 1 0 1
default : { break; }
//because PIN_A4 is open Drain output must be toggle from it should be
}
}
//========================================LCD==================================
void busy_strobe(void)
{
OUTPUT_LOW(EN);
delay_us(2);
OUTPUT_HIGH(EN);
delay_us(2);
}

void write_strobe(void)
{
OUTPUT_HIGH(EN);
delay_us(2);
OUTPUT_LOW(EN);
delay_us(2);
}

void Command(void)
{
OUTPUT_LOW(RS);
OUTPUT_LOW(RW);
}

void wait_for_lcd_ready(void)
{
unsigned char busy_flag;

SET_TRIS_C(0XFF); //PORTD7 INPUT;
OUTPUT_LOW(RS); //SET FOR READ BUSY;
OUTPUT_HIGH(RW); //SET FOR READ BUSY;

busy_strobe();
busy_flag=(input_C() & 0x80);

while( busy_flag == 0x80)
{
OUTPUT_LOW(EN);
busy_strobe();
busy_flag=(input_C()&0x80);
}

OUTPUT_LOW(EN);

SET_TRIS_C(0x00); //PORTD7 OUTPUT;
}

void clear_lcd(void)
{
Command();
OUTPUT_C(0x01);
write_strobe();
wait_for_lcd_ready();
}

void cursor_off(void)
{
Command();
OUTPUT_C(0x0c);
write_strobe();
wait_for_lcd_ready();
}

void init_lcd(void)
{
Command(); //add 240847
OUTPUT_C(0x38); //add 240847
write_strobe(); //add 240847
delay_ms(5); //add 240847

Command();
OUTPUT_C(0x38);
write_strobe();
delay_us(120); //add 240847

Command();
OUTPUT_C(0x0f);
write_strobe();
wait_for_lcd_ready();

clear_lcd();

Command();
OUTPUT_C(0x02);
write_strobe();
wait_for_lcd_ready();

cursor_off();
}

void Wchar(unsigned char char_)
{
OUTPUT_HIGH(RS);
OUTPUT_LOW(RW);

OUTPUT_C(char_);
write_strobe();
wait_for_lcd_ready();
}

void gotoxy(unsigned char row,unsigned char col)
{
Command();
if (row==1) OUTPUT_C(0x80+col-1);
else
if (row==2) OUTPUT_C(0xc0+col-1);
write_strobe();
wait_for_lcd_ready();
}

void Wcharxy(unsigned char row,unsigned char col,unsigned char data_)
{
gotoxy(row,col);
Wchar(data_);
}

void string_to_lcd(unsigned char row,unsigned char col,unsigned char *st)
{
unsigned char i,len;

len=strlen(st);
if (len>20) len=20;
gotoxy(row,col);
for(i=0;i<=len-1;i++)
{
Wchar(st[i]);
}
}

void int_to_lcd(unsigned char row,unsigned char col,int data_int)
{
unsigned char str[7];

sprintf(str,"%d",data_int);
string_to_lcd(row,col,str);
}

void long_to_lcd(unsigned char row,unsigned char col,long data_long)
{
unsigned char str[7];

sprintf(str,"%ld",data_long);
string_to_lcd(row,col,str);
}

void hex_to_lcd(unsigned char row,unsigned char col,unsigned char data_hex)
{
unsigned char str[3];

sprintf(str,"%x",data_hex);
string_to_lcd(row,col,str);
}

void float_to_lcd(unsigned char row,unsigned char col,float data_float)
{
unsigned char str[7];

sprintf(str,"%02.1f",data_float);
string_to_lcd(row,col,str);
}
//==========================================================================================

/*
int find_parity1(int data)
{
#asm
swapf data, W
xorwf data, F
rrf data, W
xorwf data, F
btfsc data, 2
incf data, F
movwf _return_
#endasm
}*/

int find_parity(int data)
{
int count;

#asm
movlw 0x8
movwf count
movlw 0
loop:
xorwf data,w
rrf data,f
decfsz count,f
goto loop
movwf _return_
#endasm
}

void main()
{
int8 data,co;
int8 checkp;

port_b_pullups(TRUE);
init_lcd();

checkp=find_parity(0b00001110);
int_to_lcd(1,1,checkp);

while(1)
{
delay_ms(1);
}
}
===============================================

Now i search follow MR. PCM programmer tell me.
and have some courcecode but i''m not sure when i translate in to CCS
Please reveiw and chang in procedure in ccs for me. Please.

below is original from web

===============================================
Parity

From: John Payson
comments from Andrew Warren of Fast Forward Engineering

;8-bit parity
;This routine will leave the parity of X in X.0
;while blenderizing most of the rest of X
swapf X, W ;x = abcdefgh w = efghabcd
xorwf X, F ;x = abcdefgh w = efghabcd
; xor efghabcd
rrf X, W ;x = abcdefgh w = -abcdefg
; xor efghabcd xor -efghabc
xorwf X, F ;x = abcdefgh w = -abcdefg
; xor efghabcd xor -efghabc
; xor -abcdefg
; xor -efghabc

; at this point, the parity for half the bits
; (a, b, e, and f) is in bit 2 of X, and the
; parity for the other half (bits c, d, g, and h)
; is in bit 0 of X.

btfsc X, 2 ; if the parity of (a,b,e,f) is 0,
; then the parity of (a,b,c,d,e,f,g,h)
; is equal to the parity of (c,d,g,h)...
; which is already in bit 0, so skip ahead.


incf X, F ; otherwise, the parity of (a,b,e,f) is 1,
; so the parity of (a,b,c,d,e,f,g,h) is
; NOT equal to the parity of (c,d,g,h).
; invert bit 0.

; at this point, bit 0 contains the parity of
; (a,b,c,d,e,f,g,h).
==============================================
and i change into ccs sourcecode like below
but when i send data is integer=14. it 's return (integer value= -9 for me )
i'm very confuse about asm and register when it use in ccs

int find_parity1(int data)
{
#asm
swapf data, W
xorwf data, F
rrf data, W
xorwf data, F
btfsc data, 2
incf data, F
movwf _return_
#endasm
}

[PCM programmer]

To fix that routine, you need to move "data" into the W register,
and then mask it down so that only bit 0 is valid. See the two
lines that I've added right above the "return" statement at the end.

[a]

thank you again. MR.PCM programmer and "ckielstra" it's work.
i will try your sourcecode and used it for my thesis. i hope u happy in this year and next year. May be. i want your help in the future. thank you very much. you are the light for me.