03-23-2018 07:14 AM
I got an error on Vivado 2016.3, I'm working on Ultrascale Virtex device
ERROR: [Place 30-68] Instance .../hda_gpio_sdi_stage_in (FDCE) is not placed
Phase 1.1 IO Placement/ Clock Placement/ Build Placer Device | Checksum: 125ac6b3
And the report doesn't give to much information about the reason why can not be placed that instance
On synthesis I do see this instance as an FDC (not FDCE), not sure if that is related
Any clue why vivado can not place this instance?
03-23-2018 09:45 AM
ok little more info:
I have a constraint
set_property IOB TRUE [sdi_port]
that sdi_port is an input that goes to the flop FDC in problem.
I have a critical warning related:
[Vivado 12-2285] Cannot set LOC property of instance 'sdi_port_iobuf', for bel IN_FF Site BITSLICE_RX_TX_X1Y152 has conflict between ISERDES CLKDIV pin, OSERDES CLKDIV pin, because the nets on those pins are not the same.
Resolution: When using BEL constraints, ensure the BEL constraints are defined before the LOC constraints to avoid conflicts at a given site.
I imagine that BEL constraint is the IOB TRUE?
will try to change the order of the constraint with respect to the LOC pin constraint
any clue from this new information?
03-25-2018 02:37 AM
Are you using Vivado synthesis? Can you please share the post opt dcp file?
03-27-2018 11:24 AM
I send you a private msg in order to upload the *.dcp
I use synopsys synthesis tool
I had a previous model working , so before I had the same clock frequency in the 3 pins of the IOB pin (I, O and T), the change I did basically is I changed the clock frequency of the flop driven by the O pin, son now I and T goes to flops of x freq, and O goes to a flop of y freq. So my guess is that is the issue, however dont understand why?
What is the rule when you put IOB=TRUE?, the tool tries to put all the 3 flops that drives I,O, T pins inside the IOB cell logic?
I noticed that when I put IOB=TRUE property , then the tool put that property to the flops of I, O and T, but sometimes only I and T flops, or sometimes only to I and O flops, so that's why I am asking what is the rule when IOB=TRUE