Wednesday, March 24, 2010

Throwing in the towel

Tonight, I had to admit that it is impossible to complete my design by the deadline this Friday.


It was all my own fault.  I threw away a month waiting to see if I'd made past the first selection to the top 100 entries. 

I wasted a second month on getting reflow soldering working.  In a couple evenings, I could have hand soldered enough boards to get debug started, then worked on the reflow in parallel. 

So I had only three weeks left for debug, but could have had eleven weeks.  Ouch, my bad.  Terrible planning.

It turns out, I also don't do my best design and debug work at 1am.  Debug was going way slower than it should have.

Here is what I debugged in one of my typical evenings, between 10pm and 2am:
  • Reset AT42QT2160 incorrectly
  • Forgot to turn on LCD backlight regulator
  • Cold solder joint on connector pin for backlight power
The first problem was that I misread the datasheet back when I coded the initialization function, and for over an hour of debug assumed my understanding was right, just coded wrong.  I mean, how hard is it to send a reset command?  Pretty easy on the QT2160 as it turns out.  I just tried to make it hard.

The second and third problems were two bugs with the same symptom - the LCD backlight wouldn't come on.  So I went round and round with that for a while before I realized there were two bugs I was dealing with.

The good news is I don't need to survive on 3-5 hours of sleep any more.  I won't give up on this project, but I'm not going to kill myself working late at night any more.  Its just not productive use of my time because I'm so inefficient that late at night.

4 comments:

John said...

Ah, pity! Maybe you can tell them the dog ate your PCB? Are you still going to submit it not quite finished?

SiliconFarmer said...

No, I decided not to submit what I had.

With only a couple days left to the deadline, I didn't even have time to hack together a partially working demo based on what was working.

Laen said...

Are you going to continue development anyway?

SiliconFarmer said...

Yes, development is continuing but at a more relaxed pace.