download from FPGA using JTAG

[booblik]

I know that you can use JTAG to program a FPGA board, but is it possible to download the contents of the FPGA, using JTAG, to the computer?
Are there any methods of getting the contents of the FPGA?

 

[FvM]

Some vendors provide configuration readback through JTAG, others don't. The option may be disabled also in the present configuration.

Other options don't exist, I fear.