Problema di drift usando una Time Loop

Sto utilizzando un sistema con:
   Labview 2012,
   sistema operativo: XP (dovrà migrare su Seven)
   NI-PXI 8106 con chassis PXI-1045
   scheda seriale Fastcom FSSC della COMMTECH
Devo utilizzare una comunicazione seriale sincrona e inviare ad intervalli di 1 msec un messaggio: a tal fine ho utilizzato una "Timed Loop" anziché una "wait";
purtroppo, da un esame con l'oscilloscopio, emerge un jitter piuttosto ampio tra un messaggio e il successivo.
Vorrei cortesemente sapere:
1) è possibile migliorare questa situazione? Se si, quali soluzioni sono possibili?.
2) una delle soluzioni a cui pensavo è utilizzare un timer hardware per pilotare il Time Loop: posso, senza il toolkit simulation, realizzare questa soluzione? Se si come posso fare?
Grazie.

Hi
How much is your drift?
Bruno Costa
Automation Engineer

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