Wie kann ich hier die Anchlusspins am PCF8574 selber festlegen und wo?

Gruss

Code:
copyright = Kent Andersson
www       = none
email     = kent@smmab.se
comment   = I2C LCD driver
libversion   = 1.02
date         = 31 march 2002
statement    = You are free to use this code any way you like, if you are able to optimize
statement    = it better, please send me an update on my e-mail.
history      = No known bugs.

;define a constant named PCF8574_LCD pointing to the I2C address
;dimension _lcd_e as byte to control the E-lines (4 lines LCD:s)
;_lcd_e should have one of the following values
;128 to enable E1, 64 to enable E2, 192 to enable both E1 and E2 (cls, deflcdchar) 
;Connect the following pins from PCF8574 to LCD
;
;P0 - D4
;P1 - D5
;P2 - D6
;P3 - D7
;P4 - RS
;P5 - RW (not used, set to 0 to ground for write)
;P6 - E2 (on 1 or 2 line display nc)
;P7 - E1

[_Init_LCD]
_Init_LCD:
 *BASIC: waitms 50
 ldi r16,&hc0       ; this is to make the initialization on both halfs of a 4-line LCD
 Ldi _temp1, &h03   ; at init-time I call all routines before _lcd_e is loaded into r16
 Rcall _Send_to_LCD
 *BASIC: waitms 4
 Rcall _Send_to_LCD
 Rcall _Send_to_LCD
 Ldi _temp1, &h02
 Rcall _Send_to_LCD
 Ldi _temp1, &h28
 Rcall _Write_lcd_byte  ;RS flag should to be 0, so jump directly to write byte
 Ldi _temp1, &h08
 Rcall _Write_lcd_byte
 Ldi _temp1, &h0c
 Rcall _Write_lcd_byte
 Ldi _temp1, &h01
 Rjmp _Write_lcd_byte
[END]


[_Write_lcd]
_Write_lcd:
* lds r16,{_lcd_e} 
 sbr r16,&h10                         ;set RS flag (4 high bits is used as control)
 rjmp _write_lcd_byte
_Lcd_Control:
* lds r16,{_lcd_e} 
_write_lcd_byte:
 push r24
 Swap _temp1                                
 Rcall _Write_lcd_Nibble 
 pop r24        
_Write_lcd_nibble:
 Cbr _temp1,&HF0                      ; E1, E2, RW, RS low

_Send_to_LCD:
push r26
push r27
 ldi r25,3
_send_3_times:
 *BASIC: i2csend pcf8574_LCD,_temp1
 eor _temp1,R16	                      ; Xor E1 and/or E2 to set them
; @genus(250)
 ldi r26,0
_LCD_delay:
 dec R26
 brne _LCD_delay
 Dec R25
 Brne _send_3_times 
 eor _temp1,R16			       ; Xor to restore to initial state (even number of times)
pop r27
pop r26
ret

[END]