I'm trying to connect my Smart Solar MPPT 75/15 to an Arduino UNO Wifi Rev2 via the VEDirect to USB cable. The 75/15 is configured for normal Tx, so as I understand it, it SHOULD be transmitting character data every second.
The Arduino sees nothing. So, I'm inclined to suspect one of the following:
1). The VEDirect to USB cable is opto-coupled, rather than inductively coupled; and the USB side of the connector requires 5v power, which the Arduino does not supply.
2). The Smart Solar does not transmit character data via VEDirect when it is operating in bluetooth networking mode.
3). The Tx and Rx pins are reversed.
Can anyone confirm/eliminate any of these possibilities, or suggest a solution? I'm tempted to direct-wire the two devices, but I'd prefer to avoid that if possible.
Thank you for your help.