I have some Industruino applications that in some cases will connect to Blynk an send eMails (if they are equipped with an Ethernet or GPRS board on their expansion port) or be content with communicating through their Modbus RTU playmates (if not).
In the latter case, I would try and find a way for my D21G to detect whether its Ethernet module or GPRS module is connected or not, so I can skip its tasks at startup (they tend to slow things a bit) and later during execution (same).
Any ideas welcome. Still diggin'
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