Maybe not
Code:
YourArray[YourCounter] = RCREG
If YourCounter !=9 then 
        YourCounter=YourCounter+1
        ELSE
        NewDataIsReady = 1 
        ENDIF
a bit of work around the above could work. IF so, then yes maybe there's a conflict between XIN and HSERIN... I don't see where, appart if a Timeout is used on both... or some Systems vars are shared... and if so, they're saved/restore by DT INTS... maybe there's one missing in DT list... but I have some reasonable doubt about it.