UID820 is digital I/O & PWM input/output controller based on the SimpleCAN protocol of UIROBOT. It has 8 multi-functional I/O ports. Two of the ports can be configured as PWM outputs. Base band and duty cycle of PWM can be adjusted through instructions real-time. A control network can be made up of just UID820, or a mixture of UID820 and UIM242 stepping controllers. For users that familiar with CAN protocol, UIROBOT provides the SimpleCAN protocol to control the whole motor-sensor-solenoid network. One upper computer with CAN-Bus gateway can manager maximum 100 UID820/UIM 242 controllers.