DL40 LED and soldering issue

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#1

–I recently soldered headers to my DL40. I was successful but had problems, untypical of my other GHI experiences; soldering on all of their other modules has always been fast, easy, and the finished products were attractive.

I’m wondering if maybe this DL40 just got a little too much solder-resist or something at the factory. All of the pads seemed to resist bonding with the solder; some of them would just hang a well-bonded bubble on the pin rather than flow into the pad. I started with lower heat and increased up to what I felt comfortable applying, so close to the CPU. I carefully re-re-re-re-re-touched-up many of them with lots of cooling time inbetween, but some still look like a first-grader did them and will forevermore… :frowning:
I haven’t tested every single pin yet, but was eventually satisfied enough, visually, to go ahead and plug it in.
Has anyone else experienced this?

–Also, in the attached clip, why does the LED on the DL40 immediately become lit and/or not dim when the neighbor bus is reset (like the PulseInOut’s does).
The DL40 appears to initialize and operate as expected; the blinking LED is being controlled by it.

Edit: ok, can’t post or embed video… here’s link
http://sdrv.ms/W8Cz98

#2

Applying flux before soldering helps a lot. The led behavior is programmed by firmware on DL40. You can make it blink anyway you like.

#3

I’ve been using silver-bearing, rosin-core solder; silver just because it was on sale. I’ll get one size thicker next time I run out.
No biggie, just odd; never had an issue before now…

FMyI, do you prefer to use a seperate flux and is there an advantage to doing so? I’ve always used rosin-core.

Ok, I incorrectly presumed that the LED feedback was part of the DaisyLink protocol.

Thanks again

#4

Sometimes I use flux. usually rosin core is enough especially if pads are pretinted.
Enjoy your DL40! :wink:

#5

Personally, on a board like this, you can never have too much flux - well I’m sure you can, but it’s much harder to get to “too much” than it is to get to “too little”. I wouldn’t bother getting thicker solder, in most cases fine solder is better than thicker (@ eevblog always says something around .6mm is preferred general purpose size). Adding flux from a flux pen or similar is ideal and will help in case the rosin core isn’t enough

#6

I’m so stupid sometimes…
Only after downloading Keil and the firmware and poking around for an hour, do I realize the LED is already a pin on a port…
Changed only ‘2’ to ‘3’ in my existing code and uploaded…