Intermec DCS 300, Руководство пользователя, Страница: 308 / 452

DCS 300 User’s Manual
10-50
About Message Types (Status vs. Transaction)
Screen and region messages can be sent to the source of the transaction as a status
message or as a transaction. A status message is text that appears in the status line at the
bottom of the terminal screen. However, some applications may expect to receive a
transaction back. For example, when you define a terminal screen field as an output
field, you need to map a transaction field to it. This transaction field can come from a
transaction message.
Transaction Message Example
You want to know how many parts you have in stock for a part number. Your Part
Query terminal screen has two fields: part number (an input field that maps to
transaction field number 1) and quantity (an output field that maps to transaction field
number 2). You also need to define a region (
QTY_RESULT
) on the Part Number
Quantity host screen at the Quantity field.
Define a message and Quantity, and then choose Transaction. In the Text field, enter:
1+”,”+QTY_RESULT
where:
1 means that transaction field number 1 contains the same value as the original
transaction field 1.
“,” is the transaction field delimiter.
QTY_RESULT
is the region that you defined. The contents of this region are sent back
to the terminal screen as transaction field number 2.
At the terminal screen, enter the part number (01234) in the Part number field and send
the transaction. When the script file receives the transaction, it performs actions to get
to the host screen titled, Query by Part Number. The part number 01234 is entered and
the Part Number Quantity screen appears and displays the value (30) you want in the
Quantity field. Part number 01234 maps back to the Part number field in the terminal
screen. The value of the quantity, 30, maps back to the Quantity field.