Arduino not showing up in Serial Port after sketch loaded

I've been playing around with my Arduino for a few years now, and this one has me stumped. I have the Pro Micro from Sparkfun, and haven't had any big problems with it. Today I uploaded a sketch, and it seems to have bricked the board. It no longer shows up in the Serial Port. I tried resetting it, holding it in reset until I reload, powering it off and on again, it just won't show up in the Serial Port. I initially assumed there was some hardware defect that had just taken hold, until I hooked up another one that worked perfectly and accepted a new sketch - until I loaded the same one that bricked my first one. Now the second one is bricked too. Any suggestions? Any idea what could cause that in my sketch? It has the following (star next to things added that weren't there when it was working fine): -Time functions (set time, calculate differences) -Serial Comms with a GPS -Parsing function with potential for endless loop -*2 x 367 element float arrays

Now whenever I reset or reboot the Arduino, the RX light blinks on for about 5 seconds, then turns off and that's it. Any ideas?

-Mac OSX 10.10 -Arduino 1.0.6 (Yes I know, was having trouble getting 1.6 to work in the first place)

Have you given the following a try?

https://learn.sparkfun.com/tutorials/pro-micro--fio-v3-hookup-guide/troubleshooting-and-faq#ts-revive

Reburn bootloader, that should fix it up in a jiffy (by removing your sketch, which is apparently clobbering it's USB communication)

Awesome, that worked! Thanks for the help. Now for the second question - any idea what sort of code could brick it in the first place? I had the board type set correctly.

That I am unsure of, I am a bit new to programming (have more experience with the hardware side of things) and only learned to diagnose problems with Arduinos after messing up mine.

I can recommend though that if the program you were working on isn't really a secret you could post snippets of the changes you made to the code leading up to the "brick" in the 'Programming Questions' subforum, you should be able to get better advice regarding that aspect of your problem there.

Good luck.

Now that I can unbrick it, I just started adding/removing code to figure out where the problem was. It was in pulling a value from the large const float array, using a variable to get the value. Here's the snippet:

sunrise[DayOfYear(year(), month(), day())]