FPGALink with Digilent Basys2 board

[112]

Hi,

I have troubles using Digilent Adept2 tools on my opensuse 12.1 64 bit
linux (it just crashes) to program my Digilent Basys2 FPGI board, so I
was looking for alternate solutions which would not require
reinstalling my system.

So is it possible to use FPGALink with Basys 2 board?

thank's

[Chris McClelland]

Hi,

1) The Basys2 is based on the AT90USB162, for which NeroJTAG firmware
exists[1], but the firmware does not yet support CommFPGA.

2) Therefore with my AVR firmware loaded into your board you would be
able to *program* the FPGA using flPlayXSVF(), but the flReadRegister()
and flWriteRegister() operations would fail with FL_PROTOCOL_ERR.

3) From a quick look at the schematic there seems to be no way to read
the existing firmware from a Basys2 board, and Digilent don't seem to
publish the firmware on their site. Therefore programming the board with
my AVR firmware should be considered an irreversible operation.

4) I have been thinking about implementing CommFPGA in my AVR firmware,
but that's unlikely to happen for a few weeks.

5) In summary: at this time I don't recommend trying to re-flash your
board with my AVR firmware, at least until I've done and adequately
tested (4) above.

6) However, a slightly less convenient (but quite cheap) alternative
approach would be to buy a Minimus[2] board for £5 and make a NeroJTAG
cable[3] with it. You would then be able to program the board using the
Minimus cable connected to the JTAG port on your Basys2, and then
communicate with it using Nexys2EPP[4]. For Nexys2EPP to work your FPGA
design (i.e your VHDL) must have been based on Digilent's dpimref.vhd[5]
or my rewrite[6] (which IMHO is better!).

Hope this helps!

Chris

[1]http://www.makestuff.eu/wordpress/?page_id=1046
[2]http://www.ck3.co.uk/minimus-avr-usb-development-board.html
[3]http://www.makestuff.eu/wordpress/?p=1927
[4]http://www.makestuff.eu/wordpress/?page_id=1016
[5]http://www.digilentinc.com/Data/Software/Adept/dpimref.vhd
[6]https://github.com/makestuff/vhdl/tree/master/dpimref