
2-16
Quadrus EZ Reader User’s Manual
RS-232 Auxiliary Port
Daisy Chain Mode
Usage:
Useful in applications where:
• More than one symbol type is present.
• A symbol may be present on multiple sides of a package.
• Symbols are presented at different depths.
Definition:
In a daisy chain application, readers are connected in tandem or “daisy
chain” and decoded data is relayed from one reader to another on up to the
host.
A master reader has its host port linked to the host computer and its auxiliary
port linked to the host port of the first secondary reader in the chain.
Thereafter, each secondary reader’s auxiliary port is linked to the host port
of the secondary reader that is further from the host in the daisy chain.
Each reader in the daisy chain can be assigned an ID that accompanies
any data that it sends.
Serial Cmd:
<
K101,aux port mode
,baud rate,parity,stop bits,data bits,daisy chain ID
status,daisy chain ID>
Options:
4 = Daisy chain
Function:
Before the master reader times out, it checks its auxiliary port for data. It
should be set to wait at least
30
mS for each secondary reader in the daisy
chain. If no data is received within the read cycle timeout, the master sends
a noread message to the host. Otherwise the complete data is sent.
If for example the master reader is set to timeout in 120 mS, the first secondary
reader downstream might be set to 90 mS, the next to 30 mS, and so forth,
thus assuring that at least 30 ms elapses between transmissions.
a
Daisy-chained readers can send a series of symbols by enabling Multisymbol
and a common multisymbol separator. If the master reader does not receive
the expected number of symbols, noread messages are appended to the
data string to make up the difference between the number of symbols
enabled in Multisymbol and the number of symbols read.
For example, a master and two secondary readers have Number of Symbols
set to 3 and Multisymbol Separator defined as %. If the master and the first
secondary reader do not find symbols, but the next secondary reader registers
a good read, the transmitted results would be: symbol data % noread %
noread.
a. The above example is based on the best case. Other factors such as baud rate, dynamic focus timing,
number of characters in a given symbol, and the number of secondary readers in the daisy chain can
affect timing and may need to be included in your calculations for complete accuracy.
Содержание Quadrus EZ
Страница 1: ...Quadrus EZ Reader User s Manual P N 83 006700 Rev T...
Страница 116: ...4 32 Quadrus EZ Reader User s Manual Background Color...
Страница 172: ...5 56 Quadrus EZ Reader User s Manual Output 3 Parameters...
Страница 186: ...6 14 Quadrus EZ Reader User s Manual Static Symbol Quality Outputs...
Страница 208: ...8 8 Quadrus EZ Reader User s Manual Service Message...
Страница 232: ...9 24 Quadrus EZ Reader User s Manual Other Camera Parameters...
Страница 252: ...11 6 Quadrus EZ Reader User s Manual Terminal Window Menus...
Страница 294: ...14 14 Quadrus EZ Reader User s Manual Ordered Output Filter...
Страница 346: ...A 42 Quadrus EZ Reader User s Manual Glossary of Terms...