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Member Since: May 15, 2006

Country: United States





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  • I mean, they’re not forcing you to buy this. They probably don’t make any money selling things for less than $2.

    They should probably sell a 5 pack for $3 or something, or sell them with resistors so Arduino users can immediately use them. That would be nice!

    Lets not just complain though, lets try to suggest improvements when we can!

  • I also just had this issue! I looked up the efuse situation in the datasheet, and basically it looks like that 0xce setting in the programming config is bad (specifically, the top 4 bits aren’t even being used, so 0xfe is the same as 0xce). I tried just fixing in in “program.txt” (efuse should be 0xfe) in the bootloader folder, but that didn’t work. However, you can “cheat” by renaming the bootloader files so that Arduino thinks its programming a 5v version, but it will program the 3.3v version. This seems to work for my home made Pro Micro clones, and it should work for a standard one too.

    Specifically, go to your Arduino sketch folder, and go to hardware/SF32u4_boards/bootloaders/caterina, then rename “Caterina-promicro16.hex” to something like “Caterina-promicro16 actual.hex” and then rename “Caterina-promicro8.hex” to “Caterina-promicro16.hex” (you may also want a “Caterina-promicro8 actual.hex” to keep track of things)

    After renaming things, you should have a copy of Caterina-promicro8.hex that is called “Caterina-promicro16.hex”, and it will be uploaded when you select the “5v” Pro micro. You can probably just modify the program.txt file, but I didn’t figure out how (restarting Arduino didn’t do it, so I just cheated).

    USB works well, and a 1 second blink appears to be 1 second, not two (didn’t time it, but didn’t much need to).

  • USB requires the accuracy of a crystal to work properly. I’m sure you can get away without it (I’m sure lufa might get away without in some instances), but for a commercial product of any kind that wouldn’t be acceptable.

  • Github often corrupts files if you don’t download them using the “download as zip” feature. Eagle libraries from the sparkfun repository don’t load in eagle if you downloaded them individually. It’s weird. No errors given, they just don’t work. Haven’t looked at a diff yet.

  • So as a professional CAD modeller I can say I’ve never heard of doing this, but I understand a lot of people use Sketchup which needs this. I’ve only tried sketchup once and never looked back - solidworks is my tool of choice, and it would actually be pretty bad in solidworks to do this, since it doesn’t use generic “Units” but actually uses mm, inch, etc units internally (unless you’re exporting STL).

    Also, for file formats STL is horrible. Can we encourage IGES or STEP if possible? Does sketchup support that?

  • And since sparkfun knows what they’re doing and they clearly do in-depth testing (see https://learn.sparkfun.com/tutorials/electronics-assembly/inspection-and-testing ), they obviously have decided that anti-static isn’t worth it. That probably means they don’t see zapped chips often enough to bother.

    It’s not like they’re a $30m a year company that excels at electronics assembly and they just didn’t think to wear anti-static stuff. I don’t do it at home and we don’t do it at my job and it’s never been a noticeable problem in either case.

  • I mean, realistically, is it? Cell phones all have better processors and often more RAM, usually in a smaller package. This is certainly a nice design, and a clearly reflects good skills on the part of the designer, but I’m not sure if I’d call it “quite an achievement” so much as good application of their skills.

  • Actually they said above that it was still well worth it. Sounded like a few days of labor was much cheaper than the cost difference between the two.

  • I would definitely wear this if it was black with a red flame outline - nerds wear black!

  • Then you missed this! http://www.sparkfun.com/news/867

No public wish lists :(