How to write to FPGA memory via jtag using self-written code?

Question

Arduino

There is an arduino as a means of writing firmware and a xilinx plis as a victim for recording.
There are a couple of codes available online. One of them successfully reads IDCODE from the plis, but can’t do anything else, the second one translates the firmware into a chip, receiving it directly from the Arduino serial port from an external device (PC). the second code is non-working, yet for an unknown reason.
There is a primitive understanding of the principles of jtag thanks to articles on Habré.
habrastorage.org/storage2/14d/361/a99/14d361a99a2d... according to the scheme, sending the logic test resets and then captcha_dr, IDCODE is read further.
How to write and where is the data register, where is the firmware stored?

Answer 1

There is an app-note on this topic, but there is an abstract MK involved.
Well, purely subjective, your question about the register with the firmware is not entirely clear. Perhaps you do not fully understand the FPGA device - there is no such thing as memory that contains a sequence of actions (firmware) as in MK. FPGA firmware is a physical connection of elementary blocks that implements the firmware.
It would be great if you could clarify your question.

Answer 2

Through JTAG, FPGAs are programmed (the firmware is loaded), this can really be done using MK by sending a JEDEC STAPL Format * .jam or Jam STAPL Byte Code 2.0 File * .jbc file via JTAG