which linux system u use?
which architecture u use? arm or mips?
do u have cross compiler?
can u compile a ftpd and install to u system?
u sys use flash rom? dload a img and boot? or use nfs root?
can u use serial port?
if u can use the serial port, i guess u generate a linux image and dload using serial port or networl to board and boot, right.
if so why not add ftp client to u img?
if u can dl u socket program to the board, u can do that.