asm source

[shannon]

Hello!
When I read the source of RTEMS, I meet these codes: 
#if ( M68K_COLDFIRE_ARCH == 1 )
#define m68k_flash_interrupts( _level ) \
   do { register unsigned32 _tmpsr = 0x0700; \
	asm volatile ( "move.w 2,%sr\n\t" \
		       "or.l   2,1\n\t" \
		       "move.w 1,%sr" \
		       : "=d"(_tmpsr) : "0"(_tmpsr), "d"(_level) ); \
   } while( 0 )

Please tell me if they are standard asm programs: 
	move.w 2,%sr\n\t" \
	"or.l   2,1\n\t" \
	"move.w 1,%sr" \
	: "=d"(_tmpsr) : "0"(_tmpsr), "d"(_level) ); \

Are there some books that explain this kind of program.


　　　　　　　　shannon
　　　　　　　　zhou_xingjian at 163.com
　　　　　　　　　　2003-08-13