Has anyone built a P!V with more than 8 cogs?

ozpropdev

Hi All
I was looking at messing around with some different hub setups and hit a wall before I even got to the hub stuff.
All attempts at generating a P1V with 16 cogs results in Quartus II 13.1 "synthesizing away" the extra cogs.

	Warning (14285): Synthesized away the following RAM node(s):
		Warning (14320): Synthesized away node "dig:core|cog:coggen[15].cog_|cog_ram:cog_ram_|altsyncram:r[0][31]__1|altsyncram_isd1:auto_generated|q_b[0]"
....multiple warnings of the same type as above

The error seems to associated with cog ram in some way, but not sure exactly why?
All pin direction/outputs and related hub select\ack signals have all been expanded to include the extra 8 cogs.
Every compile ends up with LE usage of a typical 8 cog P1V. (13% of available LE's on a DE2-115)
Rather than re-invent the wheel I thought I'd see if anyone has already succeeded in this area.
Cheers
Brian

evanh

Not that I know any HDL but I presume there is eight such warnings, one for each of Cog#8 through Cog#15. And the one you've posted is for Cog#15, right?

ozpropdev

Correct.
The warning is repeated for every cog from #8 to #15. The "FULL" compilation report is ~9000 lines long!