CONFIGURING AND TESTING STAR-System™
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Both the transactions (1 way and 2 way) must have an acknowledgement back to be
completed correctly. This assures that the application program always knows if the
data packet has been correctly delivered or not.
In case the RF device does not receive the acknowledgement packet, the transaction
fails due to timeout. Then, the device is not able to know if the data packet has
correctly arrived to the network or not.
To correctly manage this situation, you must not start a further request of an old data
packet if the previous one failed. This attempt could lead to a duplication of the data
on the application running on the host PC.
Rather the protocol gives a function to the application designer on the RF device that
must be used to retry a failed transaction instead of the normal data transaction
request.
The STAR-Link ActiveX running on the host PC signals the arrival of a data packet
from an RF device through an event and provides a method to send back a data
packet if the request is in two way mode (see relevant manual).
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