CNC shield v4.0 needs to work with Keyestudio nano ch340 . It can be used as driver expansion board for engraving machines. It has in total 3 channel slots for A4988 stepper motor driver modules (not included) for driving 3 channel of stepper motors. Each channel of stepper motor only needs 2 IO ports, which means 6 IO ports is sufficient to manage 3 stepper motors. This shield can make quick work for managing stepper motors in your project.
nano ch340 controller is a small, complete board based on the ATmega328. It’s a open source Simple I/O platform with 12 Digital I/O Pins (of which 6 provide PWM output), 8 Analog Input Pins, pin 0 (RX) and 1 (TX) used to receive (RX) and transmit (TX) TTL serial data, a Mini-B USB connection, an ICSP header and a reset button.