Sketch Will not run until com port connection is made.

i attempting drive 2 servos, , found not servo output occur until com port connection made. when looking @ output on oscilloscope, pulse not start until exact instance com port connection made.  stripped our code in setup() , loop() functions. found these 2 functions not being executed @ all, again, until com port connection made; when running simple things attachpin , delay, no serial writes, no uart comms, nothing complicated @ all.  there has changed in order allow setup function executed external power supply , not com port connection.  once com port connection made setup , loop function execute , operates needed after usb connection removed. have ideas of doing wrong?

sorry, forgot include important information. using arduino uno (atmega328)

Arduino Forum > Using Arduino > Installation & Troubleshooting > Sketch Will not run until com port connection is made.

arduino