Answers Database

M1.2/M1.3/M1.4: MAP "ERROR: x4kma:312 - Unable to obey design constraints" RAM16x1D and two flipflops


Record #2894

Product Family:  Software

Product Line:  Merged Core

Problem Title:
M1.2/M1.3/M1.4: MAP "ERROR: x4kma:312 - Unable to obey design
constraints" RAM16x1D and two flipflops



Problem Description:
Keywords: MAP, x4kma, 312, obey, constraints, RAM, FFS

Urgency: Standard

General Description:
M1.4 MAP gives the error message:
x4kma:312 - Unable to obey design constraints which require
the combination of the following symbols into a single CLB:
RAM16X1D symbol '$1I6' (output signal=$1N86) FDCE symbol
`$1I18' (output signal=WA0) FDCE symbol `$1I19' (output
signal=WA1)


Solution 1:


Map is unable to pack RAM16X1D and two FF's sharing the same
D input.

The only workaround available is to create the desired CLB
configuration in EPIC, generate a physical macro from it,
and instantiate it into your design.

For more information on creating physical macros, refer to
the (Xilinx Manual EPIC Design Editor Reference/User Guide).

Reference #: 18700



End of Record #2894