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Maybe this is the SP-ON connection? A little confused on this because the forums have a write up where it's set to serial pin 2 and the HE280 upgrade has it to the two pin connector next to the thermisters. Is this defined in the firmware somewhere?

Same problem. Monitoring terminal I get: ->Communication State: AttemptingToConnect <-start ->Communication State: Connected ->M115 (1)<-Free RAM: 879 <-Autoretract:0 <-X:0.00 etc <-SpeedyMultiply etc <-iis2dh accelerometer intializing... <-start <<repeats from (1)>>