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Hardwired and Software Controlled Systems

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Hardware is the physical parts of the computing device. If you drop it or spill a drink into it, it will break. If you drop it onto your foot, you'll curse and swear because it's often heavy or fragile. A phone is hardware.


This is the information stored on disk or flash memory pen drive. Software must be backed up or it will eventually get lost. You can send software to another person using email or by file download. The operating system, applications, music, photos and videos stored on your phone are software.

Hardware or Software

Here are some factors that need to be considered when deciding whether to use a hard wired control system or a programmable one.

Hard Wired


COST Expensive - needs custom designed circuitry. Cheap - uses a general purpose programmable chips.
FUNCTIONALITY Inflexible - every control system needs a different hard wired solution. Flexible - a single design of processor can be used in many different control systems.
UPDATING / MODIFYING Can't be modified. This is OK for simple systems that never need to be altered. Can be altered by re-programming.
RE-PROGRAMMING Not Possible. Can be re-programmed.

This is useful for control devices that may need to be upgraded or modified after maintenance work has been carried out.

A new model of an appliance might have a slightly different control program but the same controller.

STAFF EXPERTISE No need for a programmer. Hardware specialists are needed. Need a trained programmer to set up the control system. Less need for hardware experts.
RELIABILITY Mechanical control systems fail because of wear and tear on the moving parts and corrosion. More reliable because there are no moving parts. The electronics can be embedded in plastic resin to prevent corrosion.
TESTING Hardware testing is more complex and expensive than software testing. Software testing is cheaper that hardware testing for all but the most complex software projects.

Social and Economic Benefits

This list could go on and on ...




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