Lpc2000

0x00000100 represents 8 4-bit hex digits, 32 bits in all.  The right 
two digits represent the bits 0..7 so the 1 in the next digit is bit 
8 of 32 and it would set P0.8 to a 1.

To clear P0.8 do:

IO0CLR = 0x00000100;

--- In lpc2000@yahoogroups.com, "mahbub1833" <fireball003@g...> 
wrote:
>
> Hi, 
> Very newbie problem. Sorry for that. 
> 	
> 
> IO0SET = 0x00000100; /* Turn LED Off (P0.8 = 1) */ 
> 	
> 
> I didn't get the 0x00000100 in datasheet. What does it mean? How 
would 
> I understand other pin configerations as well? Please tell this 
newbie 
> in details. 
> 
> Thanks in advance.
>