B524 A7 pin acting funky


I have a problem with my B524 SoM.
I have about 20 of these devices that I am using. On about half of them the A7 pin seems to output HIGH when I put power on the device. On the other half the A7 pin outputs LOW. When the particle connects to the cloud, the A7 pin is set back to LOW. This happens even though I am pretty sure both devices are running the same firmware.

I can’t have the A7 pin outputting HIGH at startup, because the pin controls a relay.
I have tried the following code:

Even though the docs tell me that this would only influence the A6 pin. I can’t really find something that would influence the A7 pin in the docs, other than it being RESERVED.

Are half my particles using the A7 and half not, because the pin is RESERVED?
Is there a way to set the pin to LOW at startup?

Thanks in advance,


Pin A7 on the B Series SoM is the Ethernet RESET line. It’s possible that some devices have the feature flag set, which is saved to configuration flash. You can make sure it’s turned off by adding this to setup() and see if it makes a difference:

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Thanks for the reply! I’ll try it Monday. Will let you know if it works.

Worked like a charm. Thanks!

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