Rockwell Automation Allen-Bradley SynchLink 1756-DM Series Design Manual page 21

The multiplier can only transmit the same word it received (i.e. this
feature does not allow your module to receive direct word 0 and
transmit it as direct word 1). The multiplier output is limited to 16 bits;
any value generated by the multiplier larger than 65535 is truncated to
16 bits, and a Multiplier Overflow error is reported by the Synchlink
module. Make sure any data that is passed to the Output word is less
than 65535; if the data is greater, you receive incorrect output data.
Multiplier Overflow
The Multiplier Overflow bit is a data tag
multiplier value exceeds 65535. This value is set in the input data tags.
If you want to pass a Multiplier Overflow value
IMPORTANT
(received from an upstream node) to a third node
downstream but not locally change the direct word
data transmitted to the downstream node, you must:
1. Enable the Multiplier feature
2. Use a Multiplier value = 1
If you perform these steps, data received from the
upstream node on the Receive port is sent out
through the Transmit port to the next downstream
node. This process informs the downstream node
that a Multiplier Overflow condition exists upstream
and any data received is invalid.
Follow the steps described above for all SynchLink
nodes in the system that need to know about the
Multiplier Overflow condition. Figure 1.5 shows how
a Multiplier Overflow condition is sent downstream.
Figure 1.5
that is set whenever the
Publication 1756-TD008A-EN-P - August 2002
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