现场一台CPU,在正常工作的情况下，直接进入STOP模式，CPU的STOP灯亮，SF红灯亮。断电重启后又能继续运行。最近比较频繁，已经停过6次了，对生产影响较大。更换过CPU和电源模块。

有两条诊断记录不是很清楚什么意思，请大家帮忙分析一下原因。

Event 48 of 100: Event ID 16# 4546
STOP caused by CPU memory management
Previous operating mode: RUN
Requested operating mode: STOP (internal)
Internal error, Incoming event
09:41:57.980 AM 02/23/2013


Event 49 of 100: Event ID 16# 6523
Memory reset request due to error accessing memory submodule
No relevance for user (Z2): 8020 (Z3): 1410

Operating mode: RUN
Internal error, Incoming event
09:41:57.980 AM 02/23/2013


Event 50 of 100: Event ID 16# 6523
Memory reset request due to error accessing memory submodule
No relevance for user (Z2): 0000 (Z3): 0000

Operating mode: RUN
Internal error, Incoming event
09:41:57.980 AM 02/23/2013

先谢谢各位了~~