Because generating the code for LFSR counter is a computation- and memory-intensive operation, and it’s running on a server, the server usually times out after the counter value exceeds ~22 bits. I rearchitected the tool in such a way that if requested counter size is greater than 20 bit, it’s sent to a server in chunks ot 20 bits. To implement that I was using a standard AJAX approach: XmlHTPRequest and callback. That also allowed me to put a progress bar – I used  jsProgressBarHandler from Bram.us.

  Still, it’s a quite slow operation, so I limited the LFSR Counter size to 31 bit for practical purposes. There is no fundamental problem with that. It can be as large as 168 bit, it’d just take forever to complete.

I also created a stand-alone application that can generate large LFSR counters faster. Download it from SourceForge.