A circuit and method is provided that allows for communication of digital to analog data over more that one channel employing a single current switching DAC and a current switching multiplexer. Also disclosed is a sensor engageable with an end of a movable pin of a mold for monitoring the forming of a moldable part, and systems employing the same. By doing so, the firmware update system exercises control over the updates and reduce entry points exposed to attackers. Lighting conditions, size, scale, and perspective of one or more images can be adjusted. An image forming method and apparatus and a process cartridge using the photoreceptor are also provided.