Page 492 - Sensors and Control Systems in Manufacturing

Input device Output device Communications 445
Additional Keyboard Floppy disk Monitor Printer
input devices Plotter
e.g. “mouse”
Interface Interface Interface Interface Interface
Personal
Data – address – control bus computer
ROM Micro- RAM
processor
Input/Output
alignment
Sensors Actuators
24V 5V
5V 24V
A D M
D A
Process interface

FIGURE 9.6 Microcomputer standard modules.

When the development of the interactive system has been com-
pleted, the system will contain a precise image of the hardware and
the software, such as programming, memory size, ports, and number
of inputs and outputs. The microcomputer system can then be either
built as a printed circuit according to customer specifications or
assembled from standard modules (Fig. 9.6).

9.5 The Personal Computer as a
Single-Board Computer
The personal computer is not a completely new development in com-
puter evolution. It simply represents a new stage in the development
of single-board computers. A single-board computer can play a key
role in developing active communication and interfaces for worksta-
tions since it can be effectively integrated with process computer
peripherals using the following steps:
1. Inclusion of a single-board computer and power supply into
a housing
2. Replacement of the simple switch or hexadecimal input by a
keyboard similar to that of a typewriter
3. Replacement of the simple LED or seven-segment display by
a screen with 24 lines and 40 or 80 characters per line