Work in Progress Popup

Jan 2, 2019adminArt Research, Blog

Just before Christmas 2018 my fellow Computational Art MFA students at Goldsmiths, myself included, held a pop-up exhibition in New Cross High Street.

13 of us exhibited, to mark our work in progress. My interest is in surveillance, combined with an interest in breathing new life into obsolete equipment and changing their original functionality.

Item 1:

The Minitel terminal

During the Autumn term, was lucky to find a French Minitel terminal and I decided to add a real-time text feed into it. The texts were from Twitter, some speaking of subjects associated with surveillance. The equipment used to do this, in addition to the Minitel terminal, a conversion cable to adjust voltages between the Minitel and a Raspberry Pi 3 model B+. The Raspberry Pi, not only acted as a client to the Minitel but also as a server.

Alcatel Minitel 1b

Materials and methods:

I first obtained a German Minitel via eBay and this took me on a detour as the Minitel was password protected. I felt confident at the time that I would be able to unlock this machine, so I use an EEPROM reader (27C322 / 27C160 / 27C800 / 27C400 adapter board for TL866 programmer) [1]to search for the password by browsing source code downloaded from the EEPROM. I located the EEPROM on the German Minitel motherboard I looked up its datasheet[2].

I must confess, I failed in my endeavours here and the machine remains locked until I can find better use for it, it will remain as a doorstop. I was again fortunate to retrieve another Minitel, a French Alcatel manufactured c.1987 with the necessary function key and din socket to enable further experimentation.

I enclose a simple block diagram to show the layout of the dataflow. Simply put, the Minitel acting as a vt100 terminal connects to the Raspberry Pi running a batch script which enables the Minitel to login to the Pi. Having logged in, the user starts another program which will listen to another server program. The server program periodically requests search terms which are sent to the Twitter API. Open sound Control (OSC) is used to communicate between the client and server programs. This results in the tweets harvested by the server program being passed down to the client program and displayed on the Minitel terminal.

I made the simple voltage conversion cable from a design as described on the Ubuntu-fr forum and the initial scripts for the login was provided by Chapelier Fou (see references). Although the Minitel is capable of running at 4800 baud, I found the text to be too fast to read so I slowed it down to 1200 baud, make it more legible.

Not being sure that I could depend on a reliable Wi-Fi access point, I provided my own connection. A list of parts is provided at the end of this article.

In my naivete, I was unaware this combination of Minitel and displaying tweets is really nothing new for example, on June 29th, 2012, marking the end of the Minitel era, one person did exactly that. A funeral party thrown for the wake of the Minitel – a pioneering system that anticipated the Internet 10 years ahead of its time.[3]

A processing sketch runs requests to the twitter API; careful not to request more than one search term per minute otherwise I would be blocked from further requests if this was exceeded.

In order to access the twitter API I opened a developer account and was granted permission to use the twitter API on a limited basis. Instructions on how’s this is achieved is found on developer.twitter.com.

The Minitel, having no memory for itself, required a combination of the following keys being pressed:

Func-T A (80 column mode)

Func-T E (echo off)

Func-P 4 (to change to 4800 baud – if not used it stays at default 1200 baud)

Typing in

Startup script for Minitel to log into the Raspberry Pi, (residing on the Pi itself)

Typing ./start.sh will run the getty_mntl.sh…

So that the user can log in and start the server program and client programs.

#!/bin/sh

# getty_mntl.sh

TTY=${1:-ttyUSB0}

BPS=4800

stty -F “/dev/$TTY” $BPS istrip cs7 parenb -parodd brkint \

ignpar icrnl ixon ixany opost onlcr cread hupcl isig icanon \

echo echoe echok;

while [ -e “/dev/$TTY” ]; do

agetty -c -L -i -I “\033\143” $TTY $BPS m1b-x80

sleep 1

done

called by this script, (again on the pi)

# start.sh

#!/bin/bash

./getty_mntl.sh ttyUSB0

Item 2:

The VX intercom

As part of the ongoing theme of surveillance I have an interest in using a common domestic telephone intercom. It provided me with an ideal simple platform to experiment with. Following some initial research, I made on the Internet, I explored Shodan, this is best described as an Internet of things search engine. It provides an excellent up-to-date means of obtaining metrics for (non-website) connections to the Internet. I could locate Close Circuit television cameras (CCTV) for any given area four example. It is often the case that people Will leave their digital CCTV with the default factory password and ID so anyone could View a particular CCTV feed. It was an owner is task to guess camera pass words, so I went to another site called Insecam.com. The Insecam website provides and organised set of CCTV Open for anyone to view. Camera feeds are broken down by subject, time zone etc. if required. For the sake of the pop-up exhibition I opted to selectively record various CCTV feeds. For the most part they are dull, and I decided to edit them into very short snippets as the viewer may have a short attention span. As well as recorded snippets from Insecam, I included perfume webcam recordings from porn sites.

Materials and methods

I used a Raspberry Pi 3 model B plus to display the CCTV footage into the videophone. The video phone itself would only accept analogue video and therefore I would have to configure the Pi to send composite video from the special jack socket rather than via HDMI. To achieve this, I edited the start-up configuration file on the Pi as follows:

Forcing the Pi to output composite video:

In /boot/config.txt

Comment out

hdmi_force_hotplug=1

changed to

#hdmi_force_hotplug=1

And add

hdmi_ignore_hotplug=1

also change

#sdtv_mode=0

sdtv_mode=2

(PAL mode)

/boot/config.txt can be directly edited using

sudo nano /boot/config.txt

or by pressing shift on starting the Pi and editing the config.txt using that route.

The power and composite video was accessed directly on the Videx Intercom itself. The Intercom using 12V to run it and a cable was made to link the AV to the Pi and 12V to a power supply. The ground was common to the Pi and the power supply[4].

The complete assembly; power supply, LCD screen and 2 Raspberry Pi’s were mounted on a recycled steel panel taken from an old PC. I included an LCD screen because I wanted to make it easier in setting up the installation and also to display the processing sketch as it gets the Twitter feed.

I had to overclock the Raspberry Pi and fit fans onto the case of each Pi. This was in order to maintain a Temperature below 36° otherwise the CPU would be throttled, and the images would be very jerky.

Both items were mounted on the wall of the gallery at eyelevel.

Reactions:

It was apparent from the reactions to visitors at the gallery that many were unfamiliar with the Minitel terminal and it was pleasing to witness their amusement at it working. Beyond that, I doubt whether it had any further merit. I was personally happy that I had fulfilled my own modest ambition to get the Minitel working again. I have taking a great deal of interest in the subject and have read the recently published book by Julien Mailland and Kevin Driscoll “Minitel Welcome to the internet”.

An unexpected side-effect in preparing the piece was the amount of Time exploring the CCTV material itself. I spent hours looking through car parks traffic junctions in remote towns the other side of the world, marketplaces, cafes, shops, advertising hoardings and so on. I witness the homogeneity of the banal buzz of human activity peering through my solitary ghostly ‘Cyclops eye’ at snow driven car lots and the backyards of forgotten places. It made me think, if god watches over all of us, what a dull existence it must be and perhaps god would have to create suffering to break the boredom.

A Criticism was raised to me as to why I include porn clips in the material. Just as CCTV is installed to protect the property of individuals it can also be used to directly generate income streams. The money flow justifies the camera; only, the difference between voyeurism and checking on your employees and customers in order to reduce theft and showcasing flesh is that one is designed to attenuate loss and the other to profit from others loneliness.

A deeper study of the use of technology and how it erodes privacy brings to mind more sophisticated methodologies combining facial recognition with big data. Tracking individuals and picking up undesirable activity and people is already used by government to prevent crime and terrorism. Indeed, in China for example, the activity people tracking does not end at CCTV it is merely a part huge effort to watch over its citizens using social media an Internet meta data as part of the mix.

Code for project found at:

https://github.com/jtreg/popup_show

References:

https://blog.uggy.org/?post/2015/02/22/Minitel-et-Raspberry

https://tonyisageek.blogspot.com/p/telic-alcatel-minitel-running-as-usb.html

https://pila.fr/wordpress/?p=425

https://www.eevblog.com/forum/blog/eevblog-411-minipro-tl866-universal-programmer-review/775/

https://minipro.txt.si/index.php?title=Unofficially_Supported_Chips

https://spectrum.ieee.org/tech-history/cyberspace/minitel-the-online-world-france-built-before-the-web

https://hackaday.com/2011/05/22/shoehorning-rs-232-into-a-minitel-terminal/

https://bildschirmtext.btx-informationen.rehbein.net/

https://forum.ubuntu-fr.org/viewtopic.php?id=149095