Posts in Category "Central"

Central Pro loops during processing

Sometimes you will find that after some edits in your form, or on inclusion of certain data, Central will enter an infinite loop whilst processing pages.

This could have a number of obscure causes, but the most common is this: a combination of incorrect placement of $POSITION field; inappropriate subform size; and Page Full settings configured to conditionally start new pages.

The $POSITION field

When a subform is drawn on the page, the metaphporical drawing head returns to the leftmost part of the printing area, and slightly lower, ready to draw the next subform.

If the subform contains a $POSITION field however, the writing head will start drawing where the position field as, as if that position field were its {0,0} coordinates.

If a $POSITION field is in a JFMAIN page (which serves as the template page for other pages) then it will determine where the start of drawing is located.

The Page Full settings

As subforms are placed on the page, the page fills up, eventually reaching the bottom. Page Full settings can be used to determine when to skip to another page, for example, when there is no more room for a new subform instance, as well as some extra subforms (for example, footers, defined on “At End-Of-Page”).

When the page is full, a new page starts, and the subform that was going to be placed on the previous page is instead placed on the new page. It is important to note that when this is done, the page-full conditions are run again.

The subform size

If a subform is too big for the printing area, it will be truncated at the bottom (print off the bottom of the page) before a new page is started, unless the option “Reserve space for the current subform plus these subforms” option is ticked in the subform’s properties, under Page Full.

If the Reserve Space option is ticked, a new page will be started, and the subform will again be laid down on the page.

Now imagine these scenarios:

a) There is no room on the page for the subform, so a new page is started. The $POSITION field is low enough on the page so that there is still no room for the subform. So a new page is started, where the $POSITION field is again too low.
–> Infinite loop

This often happens when a $POSITION field in a JFMAIN has been moved too low for some reason. Bring the $POSITION field back to the top left corner of the printable area.

b) A large subform whose veritcal size exceeds that of the page is called. A new page is started for the subform, but the page is still too small. So a new page is started, but the page is still too small.
–> Infinite loop

This often happens when either the $POSITION field is set too low, or when the form design was made for the PDF default presentment target (it makes use of the whole page space), but the processing is done for a physical target (for example, a printer), where physical margins reduce the printable area. To correct this, set the default presentment target to be the one with the most restrictive margins (which will show in the design area as dark gray), and only allow items to be as tall as that space (remember to also account for header and footer spaces), and adjust the $POSITION field accordingly.

Many bad pages are printed / data is missing (Central Pro, Output Designer)

When processing a template with data in one environment (in Output Designer for example, or on the development server), the output seems fine; but when the same data and template are tested somewhere else (a different Designer, a different Central server), the reult is that many pages are printed, some blank, some with data in the wrong place, some data lacking.

Solution #1 – the afxon option is not properly specified

This is most likely to be due to a single argument that has been omitted in your processing parameters : “-afxon

From the Print_Ag.pdf documentation file:

To discard data for unknown fields, start Print Agent with the -afxon option.
To place data for an unknown field in the next field on the template, start Print Agent with the
-afxoff option. This is the default.

In Output Designer, these options are set under menu [ Tools : Options : Print options ]. You can add here any number of command line arguments, separated by spaces, that will apply whenever Test Presentment is run.

In Central server, arguments can be placed at two different locations

1) In the Job Management Database

You can access this under [Central install directory]/Server/jfserver.jmd

Note the syntax of the JMD: the list of arguments holds on a single line, enclosed in quote marks. Within this string of characters, double quotes must be escaped by typing two consecutive double quotes.

I posted previously about checking JMD validity – if you have Python 2.x installed, you might want to try out the following: Tamble JMD 0.2a

2) In the data file

You can add arguments in the JOB line of your data file.

If the first line of a data file starts with ^job, the Central engine (if run using Central Control on Windows, or launching the jfdaemon or jfserver on *nix) will take the arguments listed and append them to the ones already extant in the JMD. Since they are applied afterwards, they take precedence.

So if you have an argument -afxoff in your JMD, and you specify -afxon in your JOB line, -afxon will be applied when processing.

Solution #2 – you are using non-SAP compatible templates on a Central activated for SAP data

You may find that the above solution does not seem to apply (but please, test that one first as it is the most likely). In which case, there is a second potential explanation.

Central Pro can be obtained with an SAP adapter which needs to be used with templates specially compiled for this use. To activate this special compilation mode, you need to set the value of the following key to “0″

HKEY_CURRENT_USER\Software\Adobe\Output Designer 5.x\5.x\JfDesign\Compile\

Where ‘x’ should be replaced accordingly to correspond to your version of Output Designer. You can see in your problematic template whether the option is already active by looking at the template’s automatically generated preamble – if there are no !FldNotAvail events on the fields, the option is active.

“Invalid options on ^subform command” error (Adobe Central Pro)

Here’s a puzzler that looks strange, but that is easy to solve – once you understand a key difference between dynamic templates and static templates, and how Central loads and unloads tempplates.

Situation:
- You have multiple templates that you want to use for processing data
- You can process each template independantly without troubles (data only uses one template)
- When you call different templates (data uses the ^form command), with some combinations of files, you get the following error:
Invalid options on ^subform command

Reason:
You are mixing dynamic templates with static templates

Fix:
Ensure all your templates are fully dynamic by ensuring all fields exist inside subforms

Explanation:
Some of your forms are dynamic, some of them are static. Dynamic forms are created when fields are wrapped in subforms.

Dynamic forms, when compiled, create an embedded Preamble (see this in Output Designer with Ctrl+R, when a form is open)
Static forms do not.

The preamble is basically a set of variable definitions that get stored to a special global variable area.
Preamble variables call subform definitions, which are effectively the structural parts of the template.

When a template is loaded, preamble data is executed which reference form structures – for example, if you have a field called myfield in a subform called mysub, you will get:

^comment -----------------------------------------------------------------
^comment Subform: (mysub)
^comment -----------------------------------------------------------------
^define group:myfield!FldNotAvail \groupG_mysub\fieldmyfield.
^define group:myfield!FldUsed \groupG_mysub\fieldmyfield.

When a new template is loaded, any pre-existing form structures are flushed from memory (the item referred to by the “\groupG_mysub\fieldmyfield” part) – but the global preamble variables (the “group:myfield!FldNotAvail” part) are not : they cannot be distinguished easily from regular data, so they are kept.

When you load a static form, no preamble data exists to overwrite previous preamble information – in this case, the definitions for myfield field.

When in your data, myfield is called for the static field, the dynamic definition is still in memory, causing it to try and access a non-existing structure – hence the error.

A short term solution would be to wrap myfield into a subform – this will cause a dynamic preamble to be created for it, overwriting the other template’s definition of myfield

Long term, the recommendation is
-when using multiple templates, avoid where possible having fields of the same name, across all templates
-do not mix static templates with dynamic templates – if such a situation arises, convert the static forms to dynamic, by grouping them in the appropriate subforms. Preferably, leave no field out of a subform

2D Datamatrix barcodes in ZPL printing with Central Pro Output Server

You may find that when producing a 2D Datamatrix barcode for ZPL printers, the barcode is incorrectly produced. This is linked to the fact that Central’s escape character for the FNC1 control character is also part of ZPL’s “special characters” set. It is possible (and necessary) to customize the escape control character for the FNC1 byte. Configuration for 2D Datamatrix barcodes for ZPL is defined in …\Adobe\Output Designer 5.x\Config\barcode2.zpl

At the end of the file, the comments state:

; 2nd white value - escape control character
; Number representing the ASCII value of
; Zebra escape character used in the
; data.  Not currently supported.

Changing the value however will take effect correctly (ignore the fact that it says “unsupported”). To do this:

  1. In the barcode2.zpl file, edit the BarcodeWhite line appropriately of the 2D Datamatrix barcode section at the end of the file, above the comments, and save. For example, to use the dollar sign “$” as an escape character, edit as follows:
    BarcodeWhite 6 36 1 1 1

    Where 36 is the ASCII value for the dollar sign character. It is advised to remain with 7-bit ASCII values

  2. Open your form design in Output Designer
  3. go to menu File > Presentment Targets
  4. Select the presentment target (be sure it is highlighted)
  5. Click on the Font Setup button under the list of targets
  6. Make sure the correct fonts are selected – in this case, Barcode2 should be selected (if afterwards this does not work, try selecting all fonts – this will cause a bigger MDF though) Click OK to cause the changes in the barcode2.zpl file to take effec
  7. Re-compile the form to MDF; use this new MDF with your data.

2D Datamatrix barcodes should now come out fine.