Preamble
A "Preamble" is a
The default is no preamble. To select a preamble, scan up to 15 characters from the "FULL ASCII MENU" on the back of the Reader Setup Menu, and then scan SET when you're done. To return to the no preamble setting, scan CLEAR here instead of scanning SET or any characters from the FULL ASCII MENU.
You can trim
| Bar Code Data | Preamble | Data Transmitted |
| 123 | XYZ | XYZ123 |
| 12345678 | ~3XYZ | XYZ45678 |
| 12345678 | ~9 | 12345678 |
| 12345 | ~A | ~A12345 |
| 123456 | ~5 | 6 |
You can also trim selectively by bar code type. For example, you can trim 2 characters from Code 39 and a different amount from other bar code outputs. This is done by using the bar code ID character in conjunction with the tilde. A preamble of ~b2~c1 says trim 2 characters from the front of Code 39 output and trim 1 character from the front of
For advanced PC users: Emulating special keys in the preamble: Programmers and other advanced PC users can also embed keyboard hex scan codes in the preamble, for emulation of key presses specific to their computers, such as the left shift key or F12 key. This is done by specifying the make and break hex scan codes for one or more keys enclosed in "left" and "right" apostrophes (` and ').
Make and break codes are
For example, let's say you want to emulate the left shift key. First, using the FULL ASCII MENU, you'd scan a left apostrophe, to identify subsequent characters as keyboard scan codes. Next, the
