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  3. How to fix all registers in encounter

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How to fix all registers in encounter

archive
archive over 18 years ago

Hi,

Does anyone know of any automatic way to fix all registers in encounter after CTS?

It seems like a pretty common task, and I thought I would ping the community before I start digging for a way myself.

Thanks,

Manzur. 


Originally posted in cdnusers.org by myazdani
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  • archive
    archive over 18 years ago

    proc fixCellPlc {} {
    foreach instName [dbFindInstsByCell SDFF*] {
    dbSetIsInstPreplaced $instName 1
    }
    }


    you have to change "SDFF*" to your reg master name type.

    li siang


    Originally posted in cdnusers.org by lisiang
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  • archive
    archive over 18 years ago

    Hi Manzur,

    I think it is highly advisable to preserve all the clock network (tree) once you have satisfied CTS results .

    Aside the good tcl from li siang for only FF`s ( Does your CTS covers all FF's in your desing ??), i recommend to use .
    #-- Change clock status (PLACED -> FIXED)
    changeClockStatus -clk FE_CTS_ROOT/Z -fixedBuffers -fixedNetWires -useClock

    NOTE : useClock switch has special treatment in routing ( if you specify special attributes like extra space ,top metal layers etc..)
    like Ex .
    #-- Clock routing
    setAttribute -net {@CLOCK} -weight 20 -preferred_extra_space 1

    FYI .

    -fixedBuffers

    Changes the placement status of buffers, inverters, flip-flops, and gating cells from PLACED to FIXED.

    -fixedLeafInst

    Changes the placement status of leaf instances from PLACED to FIXED.

    -fixedNetWires

    Changes status of wires in clock nets from ROUTED to FIXED.

    -fixedNonLeafInst

    Changes the placement status of non-leaf instances from PLACED to FIXED


    With Regards,
    CH.MOHAN KUMAR


    Originally posted in cdnusers.org by mohanch007
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  • archive
    archive over 18 years ago


    Hi Manzur,

    I think it is highly advisable to preserve all the clock network (tree) once you have satisfied CTS results .

    Aside the good tcl from li siang for only FF`s ( Does your CTS covers all FF's in your desing ??), i recommend to use .
    #-- Change clock status (PLACED -> FIXED)
    changeClockStatus -clk FE_CTS_ROOT/Z -fixedBuffers -fixedNetWires -useClock

    NOTE : useClock switch has special treatment in routing ( if you specify special attributes like extra space ,top metal layers etc..)
    like Ex .
    #-- Clock routing
    setAttribute -net {@CLOCK} -weight 20 -preferred_extra_space 1

    FYI.
    -fixedBuffers
     Changes the placement status of buffers, inverters, flip-flops, and gating cells from PLACED to FIXED.
     
    -fixedLeafInst
     Changes the placement status of leaf instances from PLACED to FIXED.
     
    -fixedNetWires
     Changes status of wires in clock nets from ROUTED to FIXED.
     
    -fixedNonLeafInst
     Changes the placement status of non-leaf instances from PLACED to FIXED

    With Regards,
    CH.MOHAN KUMAR


    Originally posted in cdnusers.org by mohanch007
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