Dumb Terminals And Raspberry Pis

October 19, 2016 by Brian Benchoff 17 Comments

Back in the old days, the cool kids didn’t have an Apple II or a Trash-80. The cool kids had jobs, and those jobs had Vaxxen all over the place. The usual way of working with a Vax would have been a terminal, a VT220 at least, or in the case of [Sudos]’ experiments with a Raspberry Pi, A DEC VT510, a single session, text only serial terminal.

Usually, when we see a ‘new hardware stuffed into old tech’ project like this, the idea is simply to find a use for the old hardware. That makes sense; a dumb terminal from the late 90s should be a bit rarer than a Raspberry Pi Zero. This is not the case for [Sudos]’s build. He recently came across a few Raspberry Pi Zeros at Microcenter, and looking for a use for them, he decided to turn a serial terminal into a Real Unix System™.

As you would expect from a serial terminal, connecting a Raspberry Pi and putting some awesome character graphics on the screen is as simple as a Max3232 board picked up from eBay, a WiFi dongle, and an Ethernet adapter. Connect the Pi to the terminal with a serial adapter cable, and you’re off to the races.

While the VT510 serial terminal is just about the end of the line as far as dedicated terminals go, there are classier options. The VT100 terminal, older than most of the Hackaday readership, features a port on its gigantic board, meant to connect to whatever weirdness was coming out of Maynard in the late 70s. You can attach a BeagleBone to this connector, making for a very slick stealth mod.

A Minitel Terminal As A USB Linux Terminal

May 22, 2016 by Jenny List 20 Comments

If you paid a visit to France in the 1980s the chances are you’d have been surprised to see a little brown screen and keyboard sitting next to the telephones wherever you went. At the time, it was another reason apart from the food, wine, and super-fast trains to envy our Gallic cousins. This was Minitel, their take on the cutting-edge of online data services of the day.

Minitel stood apart from similar services of the day in most other countries, because of its business model. Unlike the UK’s Prestel or West Germany’s BTX for which you had to spend significant money on a terminal, the French Minitel terminals were free. Thus in the early 1980s everybody in France was busy using videotext while most of the rest of Europe was still excited by chipping bits of flint into arrow heads. Or at least, that’s how it seemed at the time to those of us who didn’t have Minitel.

The Minitel service was finally shuttered in 2012, but the terminals can still be found. [Tony Pigram] bought one, an Alcatel Minitel 1, and made it into something useful by turning it into a USB serial terminal for his Raspberry Pi. Surprisingly the physical interface between the Minitel and the USB port is a relatively simple level shifter, but the configuration of both the Minitel and the Pi was anything but.

The problem was that Minitel terminals were meant to work with Minitel, and [Tony]’s difficulties were increased by his machine being an earlier model without the handy function key to access settings found on later terminals. A lot of research paid dividends though, and he now has what must be one of the most compact and stylish CRT serial terminals available. We can’t help noticing it has a QWERTY keyboard and English menus, it would be interesting to know which non-French market it was made for.

We’ve featured an RS-232 integration into a Minitel terminal before here at Hackaday, but if you are really interested in Gallic retro-tech take a look at our discussion of their 8-bit scene.

Chibiterm Is A Tiny Low-Cost VGA Terminal

May 13, 2016 by Jenny List 22 Comments

A common sight in the days before cheap PCs conquered the world was the dumb terminal. A keyboard and a monitor with a serial port on the back that was usually hooked up to a minicomputer or even a mainframe, these were simple devices. Anything that came into the serial port was rendered on the screen, anything typed on the keyboard was sent out through the serial port. They didn’t need to contain a microprocessor. If you are old enough, you may remember electronics magazines of the 1970s and early 1980s publishing terminal designs based entirely on 74 series logic.

The serial terminal might seem like a redundant historical footnote when viewed from 2016, but they can still find a use among those working with systems such as small embedded microcontrollers that only possess a serial port. To address this application, Hackaday.io user [K.C.Lee] has created a low-cost terminal module for a VGA monitor and a PS/2 keyboard based around an inexpensive STM32F030F4 processor.

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Serial Monitor Without A PC

April 8, 2014 by Will Sweatman 18 Comments

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A serial monitor is an easy way to debug your projects. As we step through code, it’s nice to see a “Hey! I’m working, moving to next thing!” across the monitor, and not so nice to see nothing – the result of a bug that needs debugging. This has always meant needing a PC loaded with your favorite serial terminal program close at hand.

Most of the time this is not an issue, because the PC is used to compile the code and program the project at hand. But what if you’re in the field, with a mission of fixing a headless system, and in need a serial monitor? Why lug around your PC when you can make your own External Serial Monitor!

[ARPix] built this fully functional serial monitor based on an Atmega328 and a 102 x 64 LCD display. While it doesn’t have a keyboard port like this microcontroller based serial terminal, tact switches allow access to the user interface to start and stop the reading and set the baud rate. The Atmega328 has 2K of SRAM, which is needed for the project. Apparently, 1K was not enough to handle all the data. All code, schematics and a very well done parts layout are available, making this sure to be your next weekend project!