Hi,
Apologize for the delay in response.
When you generate a JIC file, Quartus converts the .sof file into a format suitable for flash memory storage. This involves converting the configuration data in the .sof file into a binary format that can be directly written to the flash memory.
The JTAG Indirect Configuration (JIC) file carries the SRAM Object File (SOF) data plus JTAG metadata. This is for loading directly into the FPGA's Configuration RAM (CRAM) and carries the FPGA configuration file.
So, to answer your question, when you write a SOF file to a flash location using Quartus, it's not the SOF file itself that gets written to the flash memory, but rather a binary representation of its configuration data. This binary data is what the FPGA reads from the flash memory during configuration.
Hope this help.
Regards,
Aiman