Page 491 - Sensors and Control Systems in Manufacturing

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Ni ne

voltage is switched off. An electrically programmable ROM (EPROM)
could be used. Therefore, the RAM is replaced by an EPROM chip on
the PC board.
Sometimes it is necessary to develop extensive programs, thus,
comprehensive knowledge and considerable experience are needed.
Programs in machine code, as a hexadecimal sequence of alphanu-
merics, are very complex, difficult to read and document, and hard to
test.

9.4 Microcomputer Interactive Development System
A microcomputer interactive development system consists of the fol-
lowing key elements as illustrated in Fig. 9.5:

• Software
• Bulk storage (floppy disk, permanent disk, or other storage)
• Monitor
• Keyboard for interaction and data entry
• Printer

In principle, there are two methods of developing the communi-
cation software for an interactive control system:

• The interactive system is located near and directly connected
to the installation workstation so that the development may
take place directly at the machine under real conditions.
• The interactive system is located away from the installation
workstation. In this case, the installation must be totally or
partially simulated, otherwise the system must be connected
to the installation from time to time.

FIGURE 9.5 Microcomputer interactive development system.