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M1.3 MAP: ERROR:x4kma:312 - Unable to obey design constraints which require the combination...


Record #2301

Product Family: Software

Product Line: FPGA Implementation

Product Part: map

Product Version: 1.3.

Problem Title:
M1.3 MAP: ERROR:x4kma:312 - Unable to obey design constraints which require the combination...



Problem Description:
Urgency: Hot

Reference #: 11202, 11585

When user has UCF location constraints file to pack unrelated H, F & G, FFS into one CLB. Map gives following error:
<OUTPUT>
ERROR:x4kma:312 - Unable to obey design constraints which require the
    combination of the following symbols into a single CLB:
      DFF symbol `DMOD_4_INSTANCE/SU_DDS/ACCLSB_REG<10>/$1I13' (output
    signal=DMOD_4_INSTANCE/SU_DDS/ACCLSB<10>)
      FMAP symbol `DMOD_4_INSTANCE/SU_DDS/DMOD_4_INSTANCE/SU_DDS/U886_MAP' (output
    signal=DMOD_4_INSTANCE/SU_DDS/N1825)
      DFF symbol `DMOD_4_INSTANCE/SU_DDS/ACCLSB_REG<11>/$1I13' (output
    signal=DMOD_4_INSTANCE/SU_DDS/ACCLSB<11>)
      FMAP symbol `DMOD_4_INSTANCE/SU_DDS/DMOD_4_INSTANCE/SU_DDS/U890_MAP' (output
    signal=DMOD_4_INSTANCE/SU_DDS/N1824)
      HMAP symbol
    `DMOD_4_INSTANCE/SU_DDS/URXSIN/DMOD_4_INSTANCE/SU_DDS/URXSIN/U262_MAP'
    (output signal=DMOD_4_INSTANCE/SU_DDS/URXSIN/N1001)
    There are more than two (2) four-input function generators. These symbols
    share the same LOC attribute, and thus must be placed in the same CLB.
</OUTPUT>


Solution 1:

Current M1.3 MAP does not support BEL(Basic Element)-based constraints such as: <INPUT>
#PLACE INSTANCE DMOD_4_INSTANCE/SU_DDS/ACCLSB_REG<11>/$1I13: CLB_R8C19.FFY;
INST "DMOD_4_INSTANCE/SU_DDS/ACCLSB_REG<11>/$1I13" LOC = "CLB_R8C19.FFY" ;

#PLACE INSTANCE DMOD_4_INSTANCE/SU_DDS/ACCLSB_REG<10>/$1I13: CLB_R8C19.FFX;
INST "DMOD_4_INSTANCE/SU_DDS/ACCLSB_REG<10>/$1I13" LOC = "CLB_R8C19.FFX" ;
..
..
</INPUT>
note the .FFX and .FFY are BEL-based constraints.

Work around:
User can create physical macro in EPIC to pack logics into one
CLB. Create a symbol for it, then instantiate it from the
design. Please refer to on-line documentation for instruction
on creating physical macros.






End of Record #2301 - Last Modified: 06/22/99 14:21

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