Answers Database

MAP M1.1.1a: -os speed causes BITGEN-DRC ERROR:0 - netcheck: no source pins found on signal


Record #1898

Problem Title:
MAP M1.1.1a: -os speed causes BITGEN-DRC ERROR:0 - netcheck: no source
pins found on signal



Problem Description:
Due to a bug in MAP, a signal driver gets left out when the -os speed
option is used.  The signal does not get optimized out because it is
not truly sourceless.  Since it does not have a driver, PAR does not
route it, so BITGEN will eventually give a simular error:

BITGEN: Xilinx Bitstream Generator M1.1.1a
Copyright (c) 1995-1996 Xilinx, Inc.  All rights reserved.
Running DRC.
ERROR:0 - netcheck: no source pins found on signal pad2XilinxCore0/n718.
ERROR:0 - netcheck: signal pad2XilinxCore0/n718 is unrouted.
ERROR:0 - blockcheck: F4 on component pad2XilinxCore0/n579 has a used term but i
s unrouted.
ERROR:0 - blockcheck: G1 on component pad2XilinxCore0/n579 has a used term but i
s unrouted.
ERROR:0 - blockcheck: F3 on component pad2XilinxCore0/n584 has a used term but i
s unrouted.
ERROR:0 - blockcheck: F4 on component pad2XilinxCore0/n582 has a used term but i
s unrouted.
WARNING:0 - DRC detected 6 errors and 0 warnings.


Solution 1:

Remove the -os speed option form the command line.
Reference BUG # 15074.



End of Record #1898