I purchased the same motor driver/controller from Robokits. I couldn't get the N1 command to work either. So, I emailed the company and they responded promptly with the follow example:
/Example for running Mitusmi Drive commands using Arduino/
void setup() {
Serial.begin(38400); // Setting the serial Baud Rate to 38400.
}
void loop()
{
Serial.print("N1 129330 10000"); // N1 Command ( N1 Position_Count Speed) // Set the position count and speed according to the motor and encoder used.
Serial.print("\r"); // Carriage Return
delay(8000); // delay to reach the mentioned postion.
Serial.print("N1 0 5000");
Serial.print("\r");
delay(8000);
}
Apparently, you need to have a single space between the N1 and position number. In the documentation it shows no space. Confusing the issue, the P command works with no space. The documentation is extremely poor, but the driver/controller is great! As I learn more, I will post here.