point to point routing with specified routing length.

Hi Suresh

The routing length can not be shorter than the manhattan length - you can check the manhattan length with the embedded procedure. By setting net attribute NR can be guided to make the routing as short as possible:

setAttribute -net <net_name> -avoid_detour true

# Procedure to report Manhattan length of a given net
###########################################
proc getManhattanLength {netName} {

    set first 1

    set netPtr [dbGetNetByName $netName]
    dbForEachNetTerm $netPtr termPtr {

        set termLoc [dbTermLoc $termPtr]
        set X [lindex $termLoc 0]
        set Y [lindex $termLoc 1]

        if { $first == 1 } {
            set min_x $X
            set max_x $X
            set min_y $Y
            set max_y $Y

            set first 0

        } else {

            if { $X < $min_x } { set min_x $X }
            if { $max_x < $X } { set max_x $X }
            if { $Y < $min_y } { set min_y $Y }
            if { $max_y < $Y } { set max_y $Y }
        }
    }

    set manhattan [expr (($max_x - $min_x) + ($max_y - $min_y)) * [dbHeadMicronPerDBU]]
    return $manhattan
}

# Procedure to report routing length of a given net

###########################################

proc getNetLength {netName} {

    set wireLength 0
    set netPtr [dbGetNetByName $netName]

    if {$netPtr != "0x0"} {

        dbForEachNetWire $netPtr segmentPtr {
            set segLength [expr [dbWireLen $segmentPtr]*[dbHeadMicronPerDBU]]
            set wireLength [expr $wireLength + $segLength]
        }
    }

    return $wireLength
}

Thanks

Khandaker

Hi Khandaker,

                     Thanks for the reply. My case is to intentionally detour the route by specified length. The length is always greater than manhattan distance.

 Regards

suresh