Some customization can be achieved -
There was a period where actual user module customization was being discussed,
see attached. I have not seen open discussion on this for several years, so beware
it may not be usable in recent Designer Releases. Consider experimenting with it.
Custom UserModules.pdf 980.9 K
I know this post is a little outdated, but still thought it would be better to provide more insight on User Module Customization.
With PD 5.3 release a lot of things with respect to Custom user modules have been simplified. For minor changes and one-time custom use, you can follow the below steps;
1. Place the user module you want to edit.
2. Set the parameters, name etc in the UM parameters/Wizard.
3. Generate the project by pressing F6.
4. After generation is complete without any errors, Right-Click on your UM in workspace explorer and then click 'LOCK'
5. Now you can edit the user module files available under "lib -> Library Source files" in the workspace explorer. These changes will not be over written by designer when generating the project again.
For creating a complete custom user module out of an existing UM, you can find details in the help section of PD 5.3. See attached image. You can simply press F1 in designer and then search for 'Custom user module', you should find details on how to do them.
Customize_UM_In_Help.png 216.5 K
Any help for 'custom user module' has been deleted or cannot be found in the help system in PD 5.4. Is it possible to place a custom high speed gate-level state-machine based user module? I can synthesize the FSM with other tools, but only if I have a model of the underlying hardware and switching choices to feed the synthesis, and a way of merging my output into the bitstream generator (a troubling prospect).
Example 1: Generating an RFID signal with digital modulation techniques.
Example 2: A custom high speed timer without all the kruft of a general purpose timer.