Is there some publicly available code for JTAG programming a MAX V (or any other device, for that matter) via a microcontroller?

Hi fzliu,

You may consider to use the open source Jam/JBC STAPL player that allow use to program the FPGA or CPLD device via JTAG interface with .jam/jbc file. For the details you may refer to the following link:

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/an/an425.pdf

https://www.intel.com/content/www/us/en/programmable/support/support-resources/support-centers/devices/programming-tools/jam-stapl/tls-jam.html

However please take note that, this Jam/JBC STAPL player is already EOL (no longer maintain). We no longer provide the support for this tool. You may use as it is since it open source.

Regards,

Nooraini