I am using Picozed (XC7Z020-1CLG400) and ARCNET module (COM20022I3V).
Picozed connected to ARCNET module via FPGA.
When using JTAG to download FPGA and program to board, ARCNET module initialized successfully.
With the FPGA and the program but using SDCARD to download, the ARCNET module does not initialize successfully.
I still have not figured out the error is due to FPGA, program or first stage boot loader.
Look forward to the help from everyone.