Hey Guys! I just wanted to reach out to any users that are having trouble getting their cores online. If your core connected to your wifi, but is fast blinking cyan forever (not green), please post here, or message me with your core id. These steps might also be helpful: [image] Troubles…

Just wanted to say, that this fast cyan can be caused with too much memory allocation on global variables in user app. For example this code will get you Core to state that can only be fixed with factory reset, or local dfu-util flash with nicer code. char tmp[4096]; void setup() { } void l…

Good call! I wonder if this improvement would help prevent these kind of heartaches in the future? [image] How to know how much RAM/Flash i am using When using the web IDE it would be great when we compile for it to show how much ram & flash the app we created is using up. right now i …

@Dave my core was working fine at my sister’s house. Then I came home and connected it to my WiFi and I am getting ‘fast cyan’ blinking. It won’t connect. My core id is 53ff6b065067544830340187

@Dave what @weakset is saying is that something as simple as allocating 4Ki of memory for a character array crashes something in the Core. In fact, I saw this same thing last night with a 2Ki buffer. That’s not going to eat up all of the 17KB or so that are available… so you won’t perceive it as a…

Exactly, but I’m not sure if there is necessarily anything wrong. Just something easy to miss even by experienced coder. When coding PC software, I tend to throw in bigger than necessary temp variables to test stuff. Too small may cause problems, but with PC there is almost infinite amount availabl…

Ahh interesting. Just having large-enough globals defined in the user firmware can interfere. This might bring us back to the RTOS / context-switching discussion that was happening in other threads, or I wonder if there might be a way to run user-firmware as a wholly separate application. – That m…

Hi @aamirjvm , Can you try clearing the wifi profiles, and smart config-ing it again? http://docs.spark.io/#/connect/troubleshooting-step-3-reboot-and-clear-memory Thanks! David

So why exactly if we have at least let’s say only 8Ki of free RAM, would a 3Ki global buffer hang up the Core, whereas a 7Ki buffer defined locally in loop() does not? I’m not seeing how bouncing back and fourth really fast between the B/G tasks and user tasks is the answer here.

I’m guessing probably that the initialization and handshake need to allocate and free a chunk of memory, which is released when they’re done. Something that isn’t used until a user-function is called would be safe since that would happen after the handshake, where a global would prevent that memory…

Holy crap how big is this handshake? xD [image]

My core never gets to breathing cyan, it's only ever 'fast cyan'

Troubleshooting

Dave January 29, 2014, 3:23pm 3

Good call! I wonder if this improvement would help prevent these kind of heartaches in the future?

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My core never gets to breathing cyan, it's only ever 'fast cyan'

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