Abstract: A method and apparatus to prevent I2C device from hanging the I2C data bus and thus stopping other devices in the system from transmitting or receiving data is presented. A logic transition detector detects a logic transition at the output data line of an I2C device and triggers a timer. The timer starts counting after it is triggered. A reset module resets the I2C interface module in the I2C device after the timer counts to a specified period of time. The timer is reset when the logic transition detector detects another logic transition at the output data line of the I2C device.

Abstract: A lens device includes a control unit, an objective lens, an image sensor, a light source, a detecting unit, and a tube assembly. The tube assembly includes a guide barrel, an outer tube, and a lens holder. The guide barrel is disposed on the control unit. The outer tube includes a tube body that is rotatably sleeve don the guide barrel, and a guiding portion. The lens holder includes a holder body having a set of projections driven by the guiding portion. The image sensor is electrically coupled to the control unit. The objective lens is optically aligned with the image sensor. The light source is coupled electrically to the control unit. The detecting unit generates a detector output indicating angular orientation of the outer tube. The control unit is responsive to the detector output to control intensity of light outputted by the light source.

Abstract: A lens device includes a control unit, an objective lens, an image sensor, a light source, a detecting unit, and a tube assembly. The tube assembly includes a guide barrel, an outer tube, and a lens holder. The guide barrel is disposed on the control unit and confines a barrel hole that extends along a barrel axis. The outer tube includes a tube body that is rotatably sleeved on the guide barrel, and a guiding portion. The lens holder includes a holder body having a set of projections driven by the guiding portion. The image sensor is electrically coupled to the control unit. The objective lens is optically aligned with the image sensor. The light source is coupled electrically to the control unit. The detecting unit generates a detector output indicating angular orientation of the outer tube. The control unit is responsive to the detector output to control intensity of light outputted by the light source.