6 years ago
gone EOL and I am trying to extend my options. The .jed file is for a C
type device, specifically the LFXP3C-3TQFP100. I need to adapt this
file to use with the LFXP3E-3TQFP100.
My understanding is that the same die is used for both devices with a
pad bonded to ground or something to indicate the internal voltage
regulators should be bypassed in the E version. It also flips one bit
in the device ID code to 0x01254043 from 0x01255043 for the C version.
A Lattice FAE told me this although he didn't seem to want to be
The .jed file does not seem to contain the ID code value anywhere in hex
or in binary. It is possible this is split over two lines which would
be very hard to search for without writing a program to read it in and
do the search.
I do see where the device name is listed in the "NOTE" section of the
file. Otherwise there is no mention of the device this goes into. As a
first attempt, I tried changing the part name in the NOTE field but that
didn't seem to work. The error reported is
Device#1 LFXP3C: Failed to verify the ID
(Expected: 0x01255043 Read: 0x01254043).
Any idea where the programmer is getting the device ID code it is using
to compare to the ID code read from the part? Is it possible it is
getting this from some other file that is in this directory? I should
try copying the JED file to a separate directory.
Any other ideas?
Just so you know, if I absolutely have to, I can recreate the .jed file
by compiling from sources. But this will be a new "design" according to
my customer and it will require the board to go through certification
again and possibly EMI testing. If I just program the E version of the
FPGA I think we can bypass all that.
-- Rick C