So you built this cool Arduino based test gear that does quality control tests on a piece of hardware. It’s time to ship to the customer, and you need to send them a sheet of paper with the test results. How do we get the Arduino to print to a printer?
Years ago, serial printers were quite common. I remember installing a lot of Okidata Line Printers connected to Unix Servers using serial cables. Those printers use a type of serial called RS-232. The signals range from +10v to -10v, which allowed long distance cabling. But how would that work with the 5v signaling the Arduino can handle?
There’s a chip called the MAX232. It’s a RS-232 to TTL Serial converter. TTL serial is the type of serial the Arduino speaks. With a inexpensive converter board, you can create statements like Serial.println(“This is printed text”); and This is printed text shows up on the printer.
All you need now is a serial printer. You can comb the catacombs of discarded computer equipment, or head over to ebay and see what they have!