修改后，但还是有问题？
OPN DB 1 // #db_no
L B#16#FF
T MB 50 //CRC_H
T MB 51 //CRC_L
L 1
T #state2
L #start
_002: T #state1
SLW 3
LAR1
L DBB [AR1,P#0.0]
L MB 51
XOW
T MB 51
_001: L MB 51
L 2#1
AW
T MB 60

L MW 50
SRW
T MW 50

A M 60.0
JCN x1
L MW 50
L W#16#A001
XOW
T MW 50

x1: L #state2
L 1
+D
T #state2
L 8
<=I
JC _001

L #state1
L 1
+D
T #state1
L #len
<=I
L #state1
JC _002