what (1<<LCRW) mean ?

Status
Not open for further replies.
K

koky

Full Member level 2
Joined
May 12, 2001
Messages
145
Helped
11
Reputation
22
Reaction score
8
Trophy points
1,298
Location
Italy
Activity points
1,097
I have found this source, but i don't understand why is used movlw (1<<LCRW)
what is the result ? why is not used a real value?

LCEN equ 1 ;rb1
LCRW equ 2; rb2
LCRS equ 3;rb3

tst_lcd_busy
movlw (1<<LCRW)
movwf PORTB
waitbusy
bsf PORTB,LCEN ; get hi-Nibble
rlf PORTB,w ; Busy-flag to Carry
bcf PORTB,LCEN
bsf PORTB,LCEN ; get lo-Nibble
bcf PORTB,LCEN
btfsc STATUS,C ;
goto waitbusy ;
return
 

Hi Koky,
I may be wrong here, but, are you sure that is not (LCRW<<1) which means shift reg defined as LCRW (2) left one bit?
Regards,
Robert
 

is : movlw (1<<LCRW)

and the software work, but i don't like use sw with strange assembler, i prefer rewrite it in more readable system
 

THIS IS A PROGRAMED SHIFT.Shift 1 left for a value writed in LCRW.It is a common use in a IAR C compiler.
EG: /* Enable receiver and transmitter */
UCSR0B = (1<<RXEN)|(1<<TXEN);
/* Set frame format: 8data, 2stop bit */
UCSR0C = (1<<USBS)|(3<<UCSZ0);
}



Greetings
Dragan
 

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…