Morovia, through the Morovia font-tools DLL, provides ease-of-integration with Sybase's PowerBuilder development toolset allowing many barcode types to be seamlessly generated from within PowerBuilder-developed applications. The purpose of this document is to create an understanding within the PowerBuilder development community on how to implement the Morovia Fontware products and the code necessary to enable those products within a PowerBuilder development environment.

Morovia enables the generation of variable-height barcodes within applications by providing two key components: (1) a series of true-type fonts that correspond to a specific height and type of barcode and (2) functions that generate a string result set based on a requested barcode value that when assigned to a field with the corresponding font, creates a barcode that matches the type and value requested. This two-step process enables PowerBuilder developers to continue utilizing the power of Sybase's patented data window technology while unleashing the means to imbed barcode values for display and printing within.

This tutorial is broken down into two components. First, steps necessary to enable the Morovia Fontware for development purposes are detailed. Second, steps required for deployment of applications written in PowerBuilder that include Morovia Fontware barcode capabilities are detailed.

In order to equip developers with the means to imbed barcode-generation features within an application, follow these few simple steps:

Step 1

Since Morovia Fontware utilizes custom fonts to generate and display barcodes, the first step is to ensure that the required fonts are installed on the computer being used for development. For instance, the fonts available for use to create UPC-A, EAN, and Bookland barcode values include: mrvUEBma, mrvUEBsa, mrvUEBta, mrvUEBxsa, mrvUEBxta. You can check to see if these fonts are already installed by going to the Control Panel and selecting Fonts.

Figure 1. Ref A.

Step 2

If the necessary font files are displayed in the list, skip this step. If they do not display in the list, this step explains how to install them. Note: Depending on the setup of the computer, administrator rights may be required to install fonts. With the correct security settings, installing fonts is a simple process. From within the Control Panel...Fonts screen, click on File and choose the option Install New Font. This will bring up an ADD FONTS explorer-style navigation window from which you can navigate to where the font-files exist on your system or network. Once the true type fonts display in the list, you can highlight the ones you need in the list by holding down the control key and clicking those needed or to select all, click on the select all button. Once the needed fonts are highlighted, click OK to add the fonts to your system. (See Ref. B)

Figure 2. Ref B.

Step 5

With the fonts successfully installed and Morovia font-tools present, you are ready to add the code components that allow PowerBuilder to interface with Morovia's font products. Generating the interface requires that an external function be defined where most appropriate for your application. External functions can be defined locally to an object or globally to the application. Most recommendations encourage limiting use of global definitions in application architecture. If using the PowerBuilder Foundation Class, we recommend considering the application manager (n_cst_appmanager) as the most appropriate place to define the local external function. This makes the function calls available to all client code. Otherwise, creating the local external function can be done in windows and objects as needed. Creating an external function is done by opening the object in which it will be created, going to the Declare Instance Variables tab, then selecting the dropdown that shows Instance Variables and choosing instead Local External Functions (or Global External Functions if you prefer). (see Ref. C)

Figure 3. Ref C.

Step 6

Define the functions to be used from the Morovia font-tools product. Once the external functions are added, save the changes. (see Ref. D). All encoder functions take a string as input and return the barcode string. Note that the function names are case sensitive and must match the ones in the DLL. For more information visit KB#10011.

Some function prototypes are listed below:

Function string UPC_A (ref string lpString) library "MRVFONTTOOLS.DLL"
Function string EAN13(ref string lpString) library "MRVFONTTOOLS.DLL"
Function string Code128C(ref string lpString) library "MRVFONTTOOLS.DLL"

Figure 4. Ref D.

Warning

In PowerBuilder 10 and above, strings are in Unicode and the prototypes must be modified so that conversion between Unicode and narrow strings is performed. You need to append Alias For at each declaration, as illustrated below:

Function string UPC_A (ref string lpString) &
      library "MRVFONTTOOLS.DLL" Alias For "UPC_A;Ansi"
Function string EAN13(ref string lpString) &
      library "MRVFONTTOOLS.DLL" Alias For "EAN13;Ansi"
Function string Code128C(ref string lpString) &
      library "MRVFONTTOOLS.DLL" Alias For "Code128C;Ansi"

Step 7

In order to generate a barcode within a data window, open a data window and identify the fields or fields that will do so. Click on the first field and identify what its current font is defined as. Change the font of the field to be the most appropriate of the Morovia fonts previously installed to the system in step 2. (See Ref. E)

Figure 5. Ref E.

Step 8

Within the code of the object responsible for creating and populating the values to be displayed in the data window, code must now be added that calls the appropriate external function with the barcode value needed. Calling the function returns a string value that should be populated into the field with the barcode font. This string value identifies for the font how the value should be displayed. If done correctly, the barcode in question should display as desired. Ref. F shows our sample window in development with the data window, a button for calculating the barcode, and a string value to the right of the button. Ref. G shows the code that will execute when the button is clicked. A UPC barcode value of 245792150797 will be passed to function UPC_A, the return string value will be captured on return, and the string value returned will be applied to field barcode_upc (defined with the UPC font). Ref. H shows the results of processing while running the window in development, after clicking the Calculate Barcode button.

Figure 6. Ref F.

Figure 7. Ref G.

Figure 8. Ref H.

Redistribution of Morovia Fontware products within PowerBuilder applications requires appropriate licensing from Morovia Corporation. Once proper licensing is obtained, there are additional terms of the licensing that must be met in order to fulfill your legal obligations under the agreement. Meeting the requirements involves registration of the fonts at runtime on the client computer and de-registration of those same fonts upon termination of your application on the client's computer. The following steps detail how these requirements can be met within PowerBuilder.

Step 1

Define two external functions within your application that interface with the windows API and allow fonts to be dynamically registered and de-registered as needed. Ref. I shows these declarations.

Figure 9. Ref I.

Step 2

Define a function within the application that can be called at the time the application runs and at the time that the application is being closed. Ref. J shows an example of such a function along with the code to be used to register and unregister fonts using the Windows API calls previously declared in Step 1 as external functions.

Figure 10. Ref I.

When installing the full version software, you run into an error message "invalid License To or Registration Code".

Morovia software require two piece of information to match the ones assigned when you install our software. One is License To, which is usually the name of the licensee, and the another is Registration Code, which is generated from License To field and encodes additional other information.

A typical screen look like below:

A common mistake is to enter Registration Code the same as the one assigned, but put a different value in the License To field. If you encountered this error message, check both fields and make sure that both matches the ones assigned.

The license information can be found in the email that we sent to you. Below shows the portion of an email that has the license information:

If you ordered a CD-ROM, you can also find the license information on the cover of the CD box.

A POSTNET barcode starts with a long bar (frame bar) and ends with a frame bar. Between these two frame bars is the encoded address information followed by a check digit. Each code character is made up of five bars, either long or short. If we use 1 to represent the long bar, 0 to represent the short bar, each character is encoded based on the table to the left.

A complete RM4SCC is made up by a set of distinct bars and spaces for each character, followed by a checksum character and enclosed by a unique Start bar, Stop bar and a quiet zone. The start bar and stop bars are unique and different; thus enable the symbol to be read in any direction. The quiet zone must be at least 2mm in each direction.

The checksum character is printed on the right hand of data characters to provide error protection. To calculate the checksum character, perform the following steps:

Note that the checksum algorithm is only performed on the main data characters contained the code. The Start and Stop bar do not participate the checksum calculation.

The customer barcode must be a continuous string of characters and must not include white space characters. The code density is 20 to 24 bars per 2.54 cm (20 ~ 24 bars per inch). For detailed requirement on barcode placement and printing requirement, refer to UK postal office.

A typical Interleaved 2 of 5 barcode has the following structure:

ITF-14 is the GS1 implementation of an Interleaved 2 of 5 bar code to encode a Global Trade Item Number. ITF-14 symbols are generally used on cartons. ITF-14 always encodes exact 14 digits.

We'll briefly review the printing features provided by the VB here. These samples show some of the most typical printing tasks you'd likely need.

Scale Mode

The ScaleMode determines the measurement unit you are going to use. You can set the scale mode to pixels, twips, inches, centimeters, points, character, and millimeters. Because of the resolution, the pixels scale mode is not portable among devices. 100 pixels appear much longer on a screen than on a printer.

EndDoc

When you print to a form or picture box, the image appears immediately. This is not the case for the printer. You must explicitly tell the printer where a page stops. Call EndDoc method when you finish all the drawings.

Printing at a specified location

If you'd like to print the barcode at a specified location, that is say 6 inch down and 1 inch over, you must set the currentx and currenty properties accordingly, as the code below:

  printer.scalemode = vbinches 
  printer.currentx = 1.0 
  printer.currenty = 6.0 

Print multiple lines

Visual Basic moves the printer cursor down a line after printing a line. Unfortunately the VB always moves the cursor to the left side of the printer. To have the lines started from the same currentx, you need to save this property and set it before calling Print:

  pos_x_save = printer.currentx 
  printer.print "line 1" 
  Printer.currentx = pos_x_save 
  printer.print "line 2" 
  printer.currentx = pos_x_save 

Parse the barcode string

The print method does not recognize line feed and carriage return characters. On the other side, the Datamatrix/PDF417 font encoder returns a single string separating lines with line feed and carriage return characters. You can specify the line separator with other strings, but the encoder always returns a single string. To get line by line you can use the split function provided by VB:

  Dim separator As String 
  Dim lines() As String 
 
  separator = vbCrLf 
  lines() = split(encoder_results, separator) 
  MsgBox "Total "  & UBound(lines) & "lines." 

The code below prints a Data Matrix barcode at a point 1.5 inches to the left edge of the page, 3.0 inches from the top. The barcode string is stored in an edit control called BarcodeEdit. Replace BarcodeEdit.Text with your barcode string.

  Private Sub Command_Print_Barcode_Click()
  'To print the barcode, we recommend using the built-in Printer object
  'Do not print to a picture box and transfer it to printer. That results
  'in a low quality barcode.
 
  'You can change it to other values to adjust the barcode size.
  Printer.FontSize = 12
  Printer.FontName = "MRV DataMatrix"
 
  'We use inch as measurement unit here.
  Printer.ScaleMode = vbInches
 
  'We want to print the barcode at point (1.5 inch, 3 inch)
  'Note - printer usually has a margin 0.25" at four directions.
  'You may consider this fact when you set the printer cursor
  Dim StartX, StartY As Double
  StartX = 1.5
  StartY = 3#
  Printer.CurrentX = StartX
  Printer.CurrentY = StartY
 
  'The Priner always go back to the left edge of the page after executing
  'a print statement. Unless we print the barcode to the left ledge of the page,
  'we have to parse the barcode string into lines, and print them one by one.
  'Fortunately, VB provides a nice helper function for this purpose.
  Dim separator As String
  Dim lines() As String
  separator = vbCrLf
  lines() = Split(BarcodeEdit.Text, separator)
 
  'Now we do the actual print line by line
  Dim i As Integer
  For i = 0 To UBound(lines) - 1
   Printer.Print lines(i)
   'Note: the Printer always go back to the beginning of the next line
   'after executing Print. We need to set CurrentX every time after printing a line
   Printer.CurrentX = StartX
  Next
 
  'EndDoc must be called to actual print
  Printer.EndDoc
 
  End Sub

A typical code 93 barcode has the following structure:

To calculate the check character "C" and "K", follow the following steps.

Table 1. Code93 Character Value Table

char	value	char	value	char	value	char	value
0	0	A	10	N	23	-	36
1	1	B	11	O	24	.	37
2	2	C	12	P	25	SPACE	38
3	3	D	12	Q	26	$	39
4	4	E	14	R	27	/	40
5	5	F	15	S	28	+	41
6	6	G	16	T	29	%	42
7	7	H	17	U	30		43
8	8	I	18	V	31		44
9	9	J	19	W	32		45
		K	20	X	33		46
		L	21	Y	34
		M	22	Z	35

You created a report using one of UFLs. When you print preview the report, Crystal Reports designer crashed. On some computers, you receive an application error Unhandled win32 exception occurred in crw32.exe.

This error happens on certain versions of Crystal Reports and on computers with DEP (Data Execution Prevention) turned on.

Earlier versions of Crystal Reports (Crystal 9.0 and 8.5) contains bug in calling COM-based UFL. When the computer has DEP turned on, this bug triggers a DEP exception.

You can either upgrade the Crystal Reports to version 10 or above, or turn off the DEP protection for crw32.exe.

To turn off the DEP protection for crw32.exe, perform the following steps:

Note: the DEP is applied on process level. If your application or some other processes call Crystal Reports dll, you need to put the location of the process into the exclusion list. Alternatively, you can disable DEP on Windows level.

KB#10002 explains how to download PCL fonts using Copy command. To use this approach, the printer must be physically connected to a computer via a parallel or USB port and shared across a Windows network. Another widely deployed solution is to connect the printer to the LAN directly using a built-in network adapter or a print server adapter. This configuration allows computers running operating systems such as UNIX and Macintosh to print using LPD protocol.

Before we go details about LPR command, it is necessary to explain two terms used in the LPR.

The example files are the same as the one in KB#10002. To download the files, visit KB#10002.

As indicated in KB#10002, you perform three steps to send the font to a printer. The first command, Font ID, assigns a unique number to the font followed. After that you send the font binary file to the printer. The last step makes the font permanently reside in the RAM by sending the Make Font Permanent command.

In our example, we store the data in three separate files: font-id.txt, code39ma.sfp, set-font.txt. We can use copy to send them in one stream. However, the LPR command does not support concatenating files. We need to combine these three files into one first and this can be done using the COPY command:

copy /b font-id.txt +code39ma.pcl +set-font.txt  total.bin 

After we combine the three files into one, we can then use lpr to send the font:

lpr -S 192.168.1.22 -P raw -o l total.bin

The option -o l is needed to send the file in binary format to the printer.^[1]

After we complete sending the font, we can send the content.txt to the printer to print a test page:

lpr -S 192.168.1.22 -P raw -o l contents.txt

Note: the lpr option “l” is the l as in “lucy”, not digit 1.

A typical code 39 barcode has the following structure:

A UPC-A number consists of four areas: (1) The number System; (2)The manufacturer code; (3) the product code; (4)The check digit. Normally the number system digit is printed to the left of the barcode, and the check digit to the right. The manufacturer and product codes are printed just below the barcode, separated by the guard bar.

A UPC-A symbol can be divided into two halves, each consisting of six digits separated by a center guard bar pattern. The whole symbol is surrounded by two guard bar patterns. The same digit has different encoding depends whether it is in the left haf or in the right half. The encoding pattern for digits in the left halve always starts with a space while the one for digits in the right halve always start with a bar and ends with a space.

A UPC-A symbol has the following structure:

UPC-A check digit is calculated using standard Mod10 method. Here outlines the steps to calculate UPC-A check digit:

A web-based free utility to calculate UPC-A check digit is available at http://www.morovia.com/education/utility/upc-ean.asp.

MSI is sometimes called Plessey Code or MSI/Plessey.

A typical MSI/Plessey barcode has the following structure:

MSI uses one or two check digits, which may be calculated in a number of different ways. As such, it is really up to the software application to implement and check the check digit(s).

The most common method of calculating MSI check digit is Modulo 10.

To calculate the modulo 10 checksum digit, use the following steps:

There is no check digit required for codabar, though some applications opt to append a check digit at the end of the message.

FedEx Airbills use a variant of codabar. A FedEx airbill number has the format of XXXX-XXXX-XXXY with an additional 4-digit format ID. The Y character is a check digit with the algorithm unknown to public. The first 12 digits is the track number. The barcode itself starts with start/stop character C and ends with start/stop character D.

A typical Codabar barcode has the following structure:

No check digit is used in Codabar symbology.

The modifier character is determined by summing the option values of each symbology. For sum less than 9, use digit 0-9 respectively. If the sum is greater than 9, use A, B, C, D, E , F in the place of 10, 11, 12, 13, 14 and 15.

An input device accepts the reflected light and converts the optical reflection into digital/analog signals. There are two major methods used for input, laser beam and CCD (charge-coupled device). CCD scanners can be very small, but they have less depth of filed than laser scanners.

A decoder decodes the symbol’s information and passes to the host computer or stores in the memory. A decodes accepts the digital signal from the input device, and converts the signals into bar and spaces. Then it quantify the element width, decode the signal based on the quantified widths. Finally, it performs some other check such as check characters. After the decoding process is complete, it transmit the data into host computer.

Decoders can be divided into two categories: on-line decoders and portable decoders. The on-line decoders use the power from AC adapter or from the computer, and the latter uses the battery.

A barcode reader usually accepts inputs of multiple symbologies. For some applications it is usually nice to know what kind of symbology the data is encoded. For this reason AIM has published a standard of prefix to describe the symbology. The prefix takes the form ]cm, where:

Currently the hardware support for this feature is somewhat limited. If your application does use this filed, you need to contact the vendor before your purchase the hardware.

This type of barcode reader is attached through the keyboard interface, the barcode reader sends data in scan codes (the codes used by IBM PC keyboards), exactly as you pressed the keys in the keyboard. It is called “Wedge reader” because they physically wedge between the keyboard and computer, as depicted the diagram below.

Since the barcode reader can use the power from the keyboard cable, no external power is needed. On the other side, this configuration is not designed for communication which has a distance more than 25 feet.

A special type of keyboard wedge barcode readers is the one using now-popular USB technology. It is similar to the keyboard wedge reader above, but uses the USB interface. No driver is needed too and the data is placed directly in the keyboard buffer. It is convenient to use with a notebook because the latter does not have an external keyboard.

Only Windows 98 or above platforms (including Windows ME, 2000 and XP) supports USB configuration. The OS treats the reader as a USB keyboard and automatically places the input in the keyboard buffer.

Keyboard Wedge interface is very simple to use. However, you must point the cursor to the correct input box and make sure that the cursor always stay in the right place before you press scan button. Theoretically a host computer can connect multiple barcode readers using this configuration, but the application has no knowledge about where the data comes from. Since the barcode reader receives power from the computer, this type of configuration does not need external power. The old application does not need to be modified to accommodate this configuration.

The barcode reader is connected to one of the serial ports of the computer. Software is needed to retrieve the information. It can be done in your application, or you place some programs coming with the barcode reader who simply reads the data and place them in the keyboard buffer. The communication takes the standard RS232 or RS432. An external power adapter is required for operation, and the distance can be as far as 250 feet. A host computer can connect as many barcode readers as the number of serial ports.

Windows provide a COM component called MSCOMM. Using this COM component your application retrieve the data from the OnComm handler. Win32 also provides serial communication APIs but this method requires advanced skills.

This type of barcode reader has memory powered by battery. Usually it also has keyboard, LCD display and is programmable. The data is stored in the memory first and then dumped into the computer via a dock station. The data is usually transmitted in a comma-delimited text file format. The dock station also acts a recharge station.

Under this configuration a RF base station is connected to the computer through keyboard wedge or serial interfaces. The barcode reader communicates with the base station via radio frequency. The transmission rates are in the 1200 to 4800 baud range. The battery usually lasts much longer than the portable batch readers.

This article provides some information on converting selected text into barcodes using barcode fonts and VBA functions.

In the first part of this tutorial, we'll demonstrate how you can create a macro that turns the selected text into a UPC-A barcode. Later on, we'll show you how to associate the macro with a keyboard shortcut or menu item so that you can invoke the macro by pressing a key or selecting a menu item.

In order to use this tutorial, you need to have Microsoft Word 2000 and above and have the Macro enabled. You will also need Morovia UPC/EAN/Bookland Fontware. If you have other linear barcode fonts package, substitute the font name and encoder function with the ones in your package. You do not need the full version - the trial version will do just fine.

Macro can be in global scope or in document scope. If a macro is placed into normal.dot template, which is loaded into every Word document, it is visible to every document. Otherwise it resides on the specific document you are working on. In this tutorial we place macro into the document we are working on. If you need to reuse the macro frequently you may consider to place into normal.dot template to make it global.

A typical code 128 barcode has the following structure: