Channel 0 Recieve Buffer not clearing.

This problem has really got me going. First off both processors are AB SLC 500. I'm ussing Chanel 0 RS233 cable to read ASCII data from a barecode scanner. Part of the programing requires that you set up your ACL "ASCII CLEAR INSTRUCTION". OK I set this to yes for the recieve buffer so that ofter each transmition the buffer is cleared and ready for the new ASCII data.
Now to the problem, two months ago all of the ASCII data that the SLC was converting to integers was corrupted. I started trouble shooting the problem by monitoring the String file that recieve the ASCII data. This Data was bad as well. To make a long story short the ACL instruction was set to NO for the recieve buffer. This happened automatically during operation. I figured it was a chance happening and thought little more about it. That was until last week when the exact same problem happened to different SLC 500 processor with the same kind of scanner and ASCII set up.
Any one herd of anything like this or witnessed a similar problem?

Thanks

I have never seen the exact same thing, but I have seen SLC 500 programs "get changed". One way is if there is an EE-PROM module present on the SLC. It could have a different version of the program that gets loaded at cold start up. Another way is if there is a sabotager who has access to the SLCs.

Your little motto that scrolls up is very annoying.

I will check the E-Prom. That sounds like the most logical solution. Sorry you don't like my quote