Microscan QX Hawk User Manual page 139

Daisy Chain Considerations
Settings for Number of Symbols and Timeout must be taken into consideration when setting
up a daisy chain configuration. An example of a three-imager daisy chain configuration and
the associated Number of Symbols and Timeout settings is shown here.
Sample setup of three imagers, each with one symbol in its field of view:
> Secondary Imager 2
# of Symbols = 1
Timeout = 100 ms
Number of Symbols
For each imager in the chain, the number of symbols set must equal the number of symbols
in the current imager's own field of view plus the number of symbols in the previous
imager's field of view. (The last imager in the chain – Secondary Imager 2 in this example
– only needs to be set for the number of symbols in its own field of view, as there is no
previous imager.)
For example, if there are three imagers and each imager has one symbol in its field of
view, the number of symbols for each imager should be set as follows:
Secondary Imager 2: # of Symbols = 1
Secondary Imager 1: # of Symbols = 2
Primary Imager: # of Symbols = 3
If there are two symbols in Secondary Imager 2's field of view, one symbol in Secondary
Imager 1's field of view, and two symbols in the Primary Imager's field of view, the number
of symbols for each imager should be set as follows:
Secondary Imager 2: # of Symbols = 2
Secondary Imager 1: # of Symbols = 3
Primary Imager: # of Symbols = 5
Timeout
The last imager in the chain passes its symbol data back in the direction of the host when
its timeout expires. Each imager must have its timeout set to acommodate its own read
time plus the read time of the previous imager.
For example, if it is determined that a maximum of 100 ms is adequate for each imager to
decode its associated symbol(s), the timeout for each imager should be set as follows:
Secondary Imager 2: Timeout = 100 ms
Secondary Imager 1: Timeout = 200 ms
Primary: Timeout = 300 ms
QX Hawk Industrial Imager User Manual
> Secondary Imager 1
# of Symbols = 2
Timeout = 200 ms
Parameters
> Primary Imager > Host
# of Symbols = 3
Timeout = 300 ms
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