各位，下面是我编写的一段程序，OPN DB 1
L P#DBX 0.0
LAR1
L MW 50
L 1
-I
L 4
*I
SLW 3
+AR1
L MD 4
T DBD [AR1,P#0.0]
但是用plcsim模拟出现故障如下：请教各位那快出现问题？我建立db1是200个双字，mw50<200.
Event 40 of 120: Event ID 16# 2523
Area length error when writing
Global DB, double-word access, Access address: 65532
OB number: 1
Module address: 196
Requested OB: Programming error OB (OB121)
Priority class: 1
Internal error, Incoming event
09:31:17.011 PM 11/22/2011