Delay() needed in loop?

Firmware
1

I’m running a cloud disabled system and had a small doubt.

Does my loop() need some sort of delay? I can’t seem to trace how functions like SPARK_WLAN_Loop() get called otherwise once I am connected (I see them getting called while it’s being setup). I’m reading through the main.cpp and how the application loop() gets called.

To be fair I am seeing the light change with connection and disconnection, but I just don’t see how this SPARK_WLAN_Loop is getting called in a connected mode with a tight (no delay) loop.

2

Nope you don’t have to worry.

The actual program is actually more than just setup() and loop() where there are a couple of flags and checks done invisible to the user

Basically, it gets called automatically depending on what you do with the connections.

Hope this helps! :wink:

3

thanks - I’ve been following those flags (I’m reading through main) but I still don’t see how if I am connected and not in setup SPARK_WLAN_Loop gets called:

https://github.com/spark/core-firmware/blob/master/src/main.cpp#L172-L207

can you help me understand that? is loop here not calling application loop?

4

I’m not entirely sure, so please correct me if I’m wrong. The way I understood it was as following: the whole Spark firmware runs as a continuous loop. Inside that loop is your sketch, which can loop as well. By defining whether or not to enable/disable wifi (or other settings for that matter) inside your sketch, you’re actually toggling them on/off inside the firmware loop.
That’s my general concept of how it works, but as I’ve said, I could be wrong.

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5

@Moors7 thanks - I figured as much too.

I think I might have misread this SPARK_WLAN_SETUP as a variable showing if we are in a sort of “setup” mode, it seems on closer reading to represent that we are already setup so main makes more sense. I think these logic variable can be a little tricky to parse as some seems to be flags, others are state.

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6

If you are wondering how the RGB led is updated if you are Cloud disabled, it gets updated via a background Interrupt Service Routine. This has nothing to do with SPARK_WLAN_Loop();

Speaking of that though… here’s some code that’s useful if you are doing serial debugging and bouncing back and fourth between cloud enabled and cloud disabled:

// Uncomment to disable the WiFi and ultimately the Cloud connection as well
//#include "spark_disable_wlan.h"

void setup(void) {
  Serial.begin(115200); // Make sure your serial terminal is closed before power the Core.
  while(!Serial.available()) { // Open serial terminal and Press ENTER.
    #ifdef SPARK_WLAN_SETUP
      SPARK_WLAN_Loop(); // Only process b/g tasks if the WiFi is enabled
    #endif
  }
  Serial.print("Hello, Sparky!");
}
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