DRO-550 PCB Construction

Step 10. Program Software and Troubleshoot

You should now program the board with the DRO-550 software with the instructions on this site.  After you finish programming the board, you can connect the power adapter like you did on the smoke test.  If you see or smell anything burning, then disconnect the power adapter from the AC.  If everything went well, then you should see a boot message and then "0.0000" on all three axes of the 7-segment display.  Here are some troubleshooting tips.

  • Problem: Nothing happens when I connect the power.
  • Action: Make sure you followed the software programming instructions exactly including setting the flash boot option.  Verify that the power adapter is supplying power by checking its DC voltage with a multimeter.  If it measures between 9-20V then it is OK.  Check the 5V power like you did in the smoke test and verify that it is in range.  Also check the 3.3V power.  If those power checks are fine, then you might want to press the PROGRAM switch with the power applied and try the programming instructions again.
  • Problem: The 7-segment display has a missing segment, digit, column, or row.
  • Action: This is almost always a poor solder connection on one of the LED displays.  Go back and look over your solder work and touch up any that don't have a nice, shiny look.  If the problem persists then it could be a failed component on the board.  If the problem is with a few individual segments, then it could be a bad 7-segment display.  If the problem is the same segment in all six columns, then it could be the sink driver IC for that row.  If the problem is an entire digit, then it could be the source driver IC for that row.  If the whole row is out, then it could be either IC.
  • Problem: The RS-232 port is not working.
  • Action: First, make sure you performed the rework on the previous step.  If it still doesn't work, then you either have the RS-232 port wired incorrectly or you are using the wrong serial parameters (baud, stop bits, etc.) with your terminal software.  Trace the connections back to the DB-9 connector and also make sure you are using a straight through serial cable to your PC and not a null-modem cable.  Verify that your terminal software is using 57600-8-N-1 serial parameters.