What is the typical motor power range in RobotC for VEX?

• A. -255 to 255
• B. 0 to 127
• C. -100 to 100
• D. -127 to 127

Answer: (D)

Motor power in RobotC for VEX is a signed 8-bit value from -127 to 127. The sign indicates direction: positive for forward, negative for reverse, and zero means stop. The magnitude tells you how fast, with 127 as full speed in whichever direction you choose. This range comes from using 8-bit signed values to command the motor, giving 255 distinct steps (including zero) and avoiding the edge case of -128 when negating values in some arithmetic operations. So for half speed you’d use around 60–64, for full forward 127, and for full reverse -127.