Broken DDR DIMM replaced, now to continue..

Replaced the broken DDR DIMM (which has a lifetimes warranty) and now to get on with things.

Trouble! Things that were working just fine, now are not

Basically the system now claims it cannot see the DDR! Which is a blow. I don't know why but I am getting the dreaded 'stack pointer not set' errors and the system doesn't seem to think it has any memory. I am wondering if I need to add in a bit more manual deskewing or whether I have actually broken something (I certainly hope not!).

More to follow....

Just connected to my first LEON3 SoC

... via the JTAG debugger but I am still unable to drive the DDR due to the lack of DCM modules in this particular Xilinx. I am now turning my attention to the XUP board from Digilent as they are quite common around here.

Hopefully I shall get further down that road towards the goal of booting linux on the system....

Trouble with the ML403...

Heh, should have realised it wouldn't be that easy...

Basically the ML403 differs from the ML401 & 2 by the fact that they both their Virtex-4's have 8 DCMs as opposed the 403's 4, and the LEON3 core with a DDR controller (necessary for the built in DDR memory) needs 5. It took a surprisingly long time for me to realise that's what the error message meant. Still today has been quite productive with a lot of lessons learnt.

Another lesson is that Xilinx ISE on windows will rebuild a Xilinx ISE on linux project, meaning the 20 minutes I took building and routing the first design came to nothing, as the windows machine proceeded to take about 60 minutes to perform the same task.