Repeatedly calling function using IPC

Hello! I'm just a beginner in developing a software.We're now
developing a software using Tcl/Tk and SKILL. We have extracted data
on schematic using SKILL function. We've transfer the data to the Tcl/
Tk using IPC.

But I have a problem. I made a funciton that will determine if the
schematic is Part2 if it contains "vdc or idc" and Part2 if it
contains "PPMU or DPS". On the first process( call of the function) it
successfully determined the corresponding Part of the schematic but if
I call this function again, the function does not gave the expected
result. What is the problem? is it in IPC or in my function.


procedure( PartChecking( strcvData )
      le( (instCellName)
                ATPPart = nil
                if( (memq("PPMU" instCellName) || (memq("DPS"
instCellName)
                            then
                                  ATPPart = "Part2"
                            else
                                 if( (memq("vdc" instCellName) ||
(memq("idc" instCellName)
                                       then
                                            ATPPart = "Part1"
                                 )
                )
     ); let
)

Hope there will help me on this thing. Thank you and God bless! : )