Driving circuit for cathode ray tube

Abstract

A microprocessor numerical control system having a prom module which contains the operating program of the system and a processor module which contains a microprocessor generating multiplexed data and address information on an internal bus. The processor module further includes bus control logic and address and data transceivers which interface the internal bus with the system's address data and control buses. The processor module further includes a variety of timing and interrupt control circuits which permits selective communication with other modules in the system. The system further includes a peripheral interface module having thereon logic to communicate with a CRT, keyboard, audible and visual indicators and an A to D converter which may be used to input feedrate override information into the processor memory. The peripheral interface module further provides interface circuitry between the processor module and a CRT display and has the capability of displaying on the display, in response to operator commands, input via the keyboard, a character display having a height which is twice that which is displayed in the normal mode of operation. The system further includes a servo output module for generating commands to drive associated motors on each of the axes of the machine tool and a transducer module which provides feedback information from these machine axes. In addition, the system further includes an input signal and an output signal module that are used to indicate and/or command the various states or modes of operation of the machine.