Geeetech

in principle，GT8 andGT9 are almost the same, except some difference in their appearances to meet the aesthetic needs of different customers. The cooling fan on the hot end is used to dissipate heat in case the filament became too soft before they get through the heater, leading to the problem of ...

ok! I will try it!

hi ,The R1 and C12 is no problem,They together is correct.
When you use marlin firmware, serial monitor can receive something, but is garbled, can prove that communication, but communication format does not match. you make sure the baud rate of marlin firmware.The line 20 it in Configuraton. H.
You ...

if you use marlin firmware ,maybe is you baudrate set error. the marlin firmware's baudrate is 250000 or 115200 ,but you computer screen capture was 9600.so please check you baudrate.

please makesure "printer settings">"printer shape">"printer type" is "Rostock printer" and "Home X,Home Y,Home Z" is MAX with Repetier Host.if you use slic3r ,Please amend the print center of 0, 0.