The main controller board

The main board is a single sided homemade pcb , it contains all necessary connectors for 3d printer components and it has extra pins for future extensions

i build this board after understanding how the RAMPS shiled works so i rearrange the pins to make the board a single sided pcb

as shown the board can control :

5 stepper drivers 

3 heaters 

4 fans 

4 servos 

6 endstops  

3 thermistors  

lcd with all buttons needed  

sd card 

and it contains a PS-on pin (to turn on the power supply ) and a serial and i2c connectors for Bluetooth or WiFi  modules ,and also it has 15 pins for any additional features to add in future 

it has a built in 5v voltage regulator to power all extensions and components except the thermistors that are powered from the arduino mega to keep them accurate .

there is fear of high load components with this board because it only controls other components with no high amps running through it.