Serial Comms in 4.6.4

[Camm]

Has something changed in the use of open , close , read , write driver
and/or  SerialControlString string in version 4.6.4.

 

I have a stack for serial comms that works fine if run in older versions of
Livecode , but fails to read in version 4.6.4

Same script ??

 

Regards

Camm