A computer spring machine is a special equipment used to produce springs. The key board, as an interactive interface of a human machine, plays the function of input operation command, editing spring processing program and modifying data, and plays an important role in the operation and control of the computer spring machine. In practical application, in order to facilitate operation, it is necessary to make the key plate chinese character and direct, which makes it unlikely to use the standard PC keyboard, so the development of a cheap and universal keyboard is very realistic.
In the PC, keyboard and host communication is ps/2 protocol, because the computer spring machine controller is a standard industrial PC controller, with a standard keyboard interface, in order to make the design simple and universal, here to use this standard keyboard interface, and the use of PS/2 protocol for keyboard and spring machine communication, design when using the microcontroller AT89S51 as a key plate processing key ingrate key recognition and data reception and transmission.
Spring machine key plate using the film panel switch form, film panel switch design is simple, easy to operate, easy to place, directly attached to a surface can be used, coupled with its water-proof and dust-proof performance, very suitable for industrial control applications. For a spring machine’s keyboard, the keys consist of three types: number keys, function keys and edit keys. The digital key of the spring machine is the input of the number, the function key corresponds to the operation command of the spring machine, and the edit key is used for editing the spring processing program, such as clear, save, etc.
A reasonable design of the key layout, universal spring machine and operation of convenience and reliability directly related, for the layout of specific keys, should consider the ease of operation and layout of the beautiful, the film panel under the row array circuit using a single-sided flexible circuit board (FPC) production, universal spring machine circuit protrusion form to ensure the feel of the keys.