Can a computer be used instead of a controller?

Question

Do it yourself

I want to automate some things in the country. For example, opening the shutters of greenhouses or watering, or a set of water at a certain time.
There are old computers available, I think here - "is it possible to use them in order to assemble a similar system without using microcontrollers?".

Answer 1

If the computer is very old, then there must be an LPT, a parallel port. There will be as many as 8 channels that can be controlled separately.

Answer 2

how to say.
there are things where the center is exactly the computer. payment terminals, for example. almost everything is based on computers with Windows. but the periphery (touchscreen, bill dispenser, etc.) has its own chip...
at least a USB-COM adapter is needed, but you can't open the sash from the COM port either :) you need at least a powerful transistor + resistor to start the motor, and if it is 220 V, then another
el.mag. relay.

Answer 3

You can also on a computer. There is an LPT port there. Even if not, you can buy a special fee . But you need to remember that the LPT port does not have galvanic isolation and your homemade product will 100% disable it.
It is better to use a computer as a server to which, via USB, sensors and executors based on Arduino

Answer 4

And for what? The computer is nice to use when you want to stay in the familiar operating environment, and this is important only if you often climb there and constantly change something there - for example, you try different options for opening these same doors.
After the algorithm is debugged, there is no point in using a computer, since, compared to MK, it consumes a lot of energy and is not very reliable.
However, if there are a lot of unnecessary computers and a rural tariff for electricity, then why not? In the usual Windows, there is support for as many as two LPT ports - these are 16 bit channels, each of which can be equipped with a 5-volt relay. And the program can be written in elementary BASIC, understandable even to a child. You can reduce heat and thereby increase reliability by reducing the processor clock speed (many motherboards allow this) and replacing the mechanical disk with a USB flash drive. This way you can even bring the computer to the complete absence of mechanical moving parts.

Answer 5

Buy an Arduino.

Answer 6

as it was already written on the arduino, everything ready
on the computer is of course more interesting,
but electricity?

Answer 7

Controllers don't seem to cost that much. But they are made for these specific tasks. Drain these computers on Avito and buy arduino \ Rpi and everything will be fine.