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The processor is designed around the PIC16F877 processor which is provided with a liquid crystal display and a miniprinter. The ports of the microcontroller are configured into 3 8-bit buses: A data bus in red, an address in blue and a control bus in green. The four lines of the control bus are expanded into a 16 line peripheral selector bus in purple. Each of these peripheral selector bus lines activates a stepper controller or a logic in/out latch. The arrangement allows the microcontroller to address any peripheral with the contents of the data bus, or read any peripheral similarly. A real-time clock provides a timebase.