hi in a different post i believed that there was a marlin firmware configuration issue so i posted in marlin, but after some investigation i believe it's hardware-related. i have CORRECTLY configured Marlin firmware 1.0.x, measured the thermistors to be 100k at 25C, yet they are BOTH - that's both the hotend AND heatbed - registering 40C in Marlin. that corresponds, according to the EPCOS NTC datasheet for the heatbed, to a resistance of 52k, which it clearly and most certainly is not.
now, i've measured the voltages at the testpads TP20 and TP22, they are 4.58 and 4.59 volts respectively, at room temperature.
could someone with a RAMBO v1.2 please do me a favour and take a voltage reading from the two same testpads? i need to verify that the voltages are correct.
many thanks.
update: the Rambo v1.2g i received is confirmed as having faulty resistor-divider circuits. exact details as-yet unknown, current hypothesis is that the OVREF circuit, or protection diodes, are suspect will keep people informed as these are otherwise great boards.
Edited 1 time(s). Last edit at 03/31/2016 08:24AM by lkcl.
