Worth Data RF Terminal 7000 - Manual (Page 26)

Other Settings
Preamble
Preambles are user-defined data that is attached to the beginning of data (bar code or keyed) that is
transmitted to the host by the RF Terminal. For example, if you set a preamble of @@ and scanned bar code
data of 12345, @@12345 would be transmitted to the host.
By default, the RF Terminal has no preambles configured. Preambles can contain up to 15 characters
entered from the keypad or scanned from the bar coded FULL ASCII Menu. To set a preamble:
1.
Select option “8” from the RF Terminal Setup menu then “1” for Preamble from the Other
Settings menu.
2.
Enter the desired characters (up to 15). Pressing the shift key will turn the cursor red to indicate that the
shift is active. Pressing shift again will turn the cursor white and return to unshifted mode.
3.
Press “ENTER”.when you are finished entering data.
4.
To clear the Preamble and return to the default (no Preamble defined), press “CLEAR”.
You can use the Preamble to trim characters from the data you are entering into the RF Terminal. You can
trim from 1-15 characters from the data by creating a preamble of:
~x
where ~ is ASCII 126 and x is a single hex digit 1-F (corresponding to 1-15). Data that is shorter than the
trim amount is transmitted without trimming. Preambles trim characters from the front of the data. Here are
some examples:
Data Preamble Data Transmitted
123 XYZ XYZ123
12345678 ~3XYZ XYZ45678
12345678 ~9 12345678
12345678901 ~A 1
123456 ~5 6
Preamble trims leading characters
Using the Bar Code ID feature and the Preamble, you can trim data selectively, trimming characters only on
the bar code type specified. To use selective trimming, enter:
~bx
where b is the Bar Code ID character (see the Code 128 setup parameter) and x is the number of characters to
trim from the front of the data. For example, ~b2~c1 says “trim 2 characters from Code 39 data and 1 character
from UPC-A data”. Remember that the Preamble trims leading data. This applies to One-Way and host
prompted communication.
Lastly, the Preamble can be used to check a minimum/maximum data length for bar code data entered. To
check for bar code length in the Preamble enter:
|nnmm
where | is ASCII 124, nn is the two-digit minimum and mm is the two-digit maximum. |0210 would check for a
minimum of 2 characters and a maxi-mum of 10. If you try to scan a bar code outside the minimum or maximum
lengths, no decode will result. Entering data by keypad is not affected.