FPGA Intellectual Property
PCI Express*, Networking and Connectivity, Memory Interfaces, DSP IP, and Video IP
6405 Discussions

Sections missing from fPLL documentation

New Contributor II

As far as I can tell, there is no dedicated documentation for fPLLs (e.g. in Cyclone 10 GX and Arria 10). Therefore, I am forced to use the limited scraps of information scattered around the Transceiver PHY user guides.

The Cyclone 10 GX Transceiver PHY User Guide is especially lacking. Section 3.1.3 looks somewhat similar to that section in the Arria 10 Transceiver PHY User Guide, except sections ("Instantiating the fPLL IP Core") and ("fPLL IP Core") are mysteriously missing.

Should I assume the Arria 10 sections apply also to Cyclone 10 GX? This seems like an altogether unsafe assumption, as there are many subtle differences between the two device families.

Needless to say, I am absolutely shocked by the state of the Intel FPGA documentation in general. It is an absolute mess. I have wasted many days of effort as a direct result of Intel's disorganized and incomplete documentation.

0 Kudos
3 Replies
Honored Contributor III

Here's the PLL documentation from the device's core fabric handbook (for C10GX): https://www.intel.com/content/www/us/en/docs/programmable/683775/current/plls.html

Is that what you're looking for?  I always start here when looking for hardware info for a specific device: https://www.intel.com/content/www/us/en/resources-documentation/developer.html#panel-for-hardware


0 Kudos
New Contributor II

Thank you for pointing out this other document. It's strange that this information is distributed across so many different documents. Unfortunately, that document doesn't contain the missing sections I mentioned (or the equivalent information). But nonetheless, there's some useful information for me to read.

I had tried using the "Resource and Documentation Center", but a search for "fPLL" doesn't show any useful results on at least the first 5 or so pages. A search for "Cyclone 10 GX fPLL" only shows the "Core Fabric Handbook" halfway through the 2nd page of results, so I don't think the search algorithm is very sophisticated.

0 Kudos


As the fPLL is used for transceivers, specific information can be found in the Intel® Cyclone® 10 GX Transceiver PHY User Guide. General PLL related usage details are provided in the handbook.


0 Kudos