DDR2 Interface in Custom Board

Hello there.

I'm have trouble assigning pins for a DDR2 interface with ALTMEMPHY on a ARRIAII-GX.

I think I may have some problems on the board traces, so I need to assign some pin locations that the fitter does not accept as part of the same memory group.

This are the error messages the fitter is giving me:

Error: Can't place DQ I/O "o_mem_dm[0]" to a non-memory interface specific I/O location PIN J18

Error: Can't place arriaii_io_pad "o_mem_dm[0]" to location "PIN J18"

Error: Can't place DQ I/O "io_mem_dq[2]" to I/O location Pin_C19 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[2]" to location "PIN C19"

Error: Can't place DQ I/O "io_mem_dq[3]" to I/O location Pin_A19 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[3]" to location "PIN A19"

Error: Can't place DQ I/O "io_mem_dq[4]" to I/O location Pin_B19 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[4]" to location "PIN B19"

Error: Can't place DQ I/O "io_mem_dq[8]" to I/O location Pin_K15 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[8]" to location "PIN K15"

Error: Can't place DQ I/O "io_mem_dq[9]" to I/O location Pin_C16 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[9]" to location "PIN C16"

Error: Can't place DQ I/O "io_mem_dq[10]" to I/O location Pin_G17 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[10]" to location "PIN G17"

Error: Can't place DQ I/O "io_mem_dq[11]" to I/O location Pin_A17 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[11]" to location "PIN A17"

Error: Can't place DQ I/O "io_mem_dq[12]" to I/O location Pin_C17 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[12]" to location "PIN C17"

Error: Can't place DQ I/O "io_mem_dq[13]" to I/O location Pin_F17 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[13]" to location "PIN F17"

Error: Can't place DQ I/O "io_mem_dq[14]" to I/O location Pin_H15 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[14]" to location "PIN H15"

Error: Can't place DQ I/O "io_mem_dq[15]" to I/O location Pin_B15 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dq[15]" to location "PIN B15"

Error: Can't place DQS I/O "io_mem_dqs[1]" to I/O location Pin_B16 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dqs[1]" to location "PIN B16"

Error: Can't place DQSn I/O "io_mem_dqsn[1]" to I/O location Pin_A16 because its memory interface I/O group cannot be placed

Error: Can't place arriaii_io_pad "io_mem_dqsn[1]" to location "PIN A16"

I've attached my pin assignments TCL file in which I've try to create Output Enable Groups for the DQ[0..7] and DQ[8..15], and DQ groups DQ[0..7] -> DQS_p[0]; DQ[8..15] -> DQS_p[1], to solve this problems, but it did not work.

I also used the same pin assigments, exept the location assigments, on a back annotate location assigments to check Group, Termination, Bidir clk to output only, etc assignments... and fitting got trough well.

So, question is: Is there anyway to bypass this error and use the memory even with a low memory clock\data rate?

Thank you!