Worth Data P11/12 user manual Bar Code Data Preamble Data Transmitted

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Preamble

A "Preamble" is a user-specified data string transmitted at the beginning of each bar code. For example, if you specify the preamble @@ and read data of 123456, "@@123456" would be transmitted to your computer.

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 1-15 leading characters from bar code codes by scanning a ~ (tilde -- ASCII 126) followed by a single digit, 1 through F (A through F are for 10 to 15), as part of the Preamble. (Bar codes which are shorter than the amount-to-trim are transmitted with no trimming.) Consider the examples in the following table to understand how trimming works:

 

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 UPC-A. Refer to the Code 128 parameter's previous discussion for a list of the ID character associated with each bar code type.

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 hardware-specific -- see the keyboard section of your computer's manual or tech references for descriptions of its make and break codes. Break codes follow one of two conventions depending on which "keycode set" a keyboard uses. Keycode set 1 (usually on XT-style systems) uses a two-digit break code formed by adding hex 80 to the make code. Keycode set 2 (usually on AT- style systems) uses two digit break codes: the first is F0 and the second is identical to the make code.

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 two-digit hex make code -- let's say it's 12. First

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Contents Worth Data WDP Keyboard Wedge Reader For Model P11/12 Introduction Installation Components of WDP ReaderExternal Wedge InstallationInternal Installation on PC P11/12 Integrated Laser WDP ReadersExternal Wedge Installation on PC or Mac USB Installation on a PC or Mac WDP Reader Setup Configuring the WDP Reader for your computer ApplicationUsing the WDP Reader Setup Menu Code WDP Setup ParametersBeep Tone UPC/EAN 5 Code 5 Data LengthDisable UCC-128/EAN-128 CodabarMSI and Plessey Computer InterfacePreamble Bar Code Data Preamble Data TransmittedPostamble MagStripe ResetData Transmission Timing Characters Keyboard CountryTerminator Characters Bar Code and MagStripe Slot Scanners Testing the WDP reader with your computerBar-code wands, laser scanners and CCD touch scanners If you are unable to read the Test LabelScanners and Scanning Technique WandsWand Scanning Technique Using the Bar Code Slot Scanner Using the MagStripe Slot Scanner Laser and CCD Scanners Worth Data LZx00 seriesClass II Laser Product CCD Scanners Tips for using CCD’s and Lasers Right WrongLaser scanner options Start SetupEnd Setup CodeFunction keys F1 through F10, and numeric-pad keys Special FeaturesFunction and Control Key Support Function keys F11 and F12Windows Key Macintosh Command and Option Keys on USBShift, Ctrl and Alt keys Accumulate Mode Troubleshooting Reader wont beep when reading bar codesReader transmits incorrect data to the screen Poor read rateChanging the volume of the WDP Readers beeper Volt power adapters for external wedge installationOpening the WDP Case ISA Internal Board Installation Slot Installation with Keyboard CablingNow turn to page 7 to configure the WDP Reader BusKey Parameters Slot Installation with Bus CommunicationInstalling BusKey BusKey P=ppp I=iJumper Settings Interrupt Number jumper JP4, the Interrupt Number jumperJP5, the Port Address jumper JP7, the Interface Method jumperJP8, the Laser Decode Light/Wand jumper JP9, the Wand/Magstripe jumperSpecifications for Code 108/43 = 2 with a Remainder Mod 43 Check Character+ 2 + 3 + 33 + 34 + 35 = Value 22 is the Check CharacterFull Ascii Extension to Code Codabar Codabar start/stop transmissionCode 128 Specifications UCC-128/ EAN-128Many of the specifications are available online at + 1 = Interleaved 2 of 5 CodeEven Odd + 9 x 3 =19873 + 48 =60 57 = 019873UPC Specifications Isbn Specifications UPC 2 and 5-character supplemental codesUPC/EAN checksum character 01234500006 UPC-E Checksum Calculation1234500006 01234565MSI/Plessey Specifications MSI Mod 10 check digit is calculated as followsMSI Mod 11 check digit is calculated as follows Code 93 Specifications Ascii Code Equivalent Table Firmware Upgrades