Is there anyone who isnīt familiar with the popular game shows on television, where the audience can cast their vote with the help of the touch of a button. "Candid Camera" and "Itīll be Alright on the Night" are examples of this. A further example is the show "Vip Vip Hoera" (pronounced "Hurra"), the new game show from BRTN, a Flemish television broadcasting company in Belgium. The program, which was launched on 26th March, represents a technical milestone for BRTN. For the first time in the history of radio and television, parallel cabling for voting by studio guests was replaced by a fieldbus. BRTN is backing INTERBUS. The aim of this step is to be able to deal with the task of repeatedly putting up and taking down the studio set more efficiently, saving time and money.
"Vip Vip Hoera", the new game show on
Belgian television, has for the first time
placed its bets on
serial cabling
Serial instead of parallel
In addition to the high-quality technology, a
matter of course in "Television", for example
cameras, mixing or transmitting devices, there
is also a great deal of high-tech to be
found in stage and set construction. Stage
and set are put up and taken down again for
each recording and stored until the next
shooting. Putting it up and taking it down
must not take much time, as otherwise the
studio is unused for too long.
In various BRTN game shows, the audience can take part with the touch of a button. A simple yes/no or true/false requires two buttons per person and a check-back indication. The latter confirms that operating the button has been accepted. Until now, the pushbutton cabling for such game shows had been parallel. A series of conductors lead from every button and every lamp to the terminal box of the control system. For a studio audience of one hundred, this means a cable with hundreds of conductors and consequently enormous installation costs. Since the studio set must be put up and taken down using a modular method, the many cables with their complicated plug connections must continuously be connected and disconnected. Hundreds of cables are led to a PLC, which is merely responsible for bundling the signals. They are then read out and sent to the PC, where the result of the vote is translated into a bar graph. In "Vip Vip Hoera", this concept of parallel cabling has not been strictly kept to. Two groups of 50 people each, each with two VIPs as team leaders, can give four answers for each multiple choice question. This means four pushbuttons and one lamp for acknowledgement per member of the audience. In order to be able to use a modular method of putting up the stage and to keep the cabling down, the decision was made in favor of the fieldbus system INTERBUS..
From the auditorium,
the audience is able
to actively participate in
the voting via INTERBUS
INTERBUS in Modules
8 INTERBUS CT 24 DIO modules were used,
each having 24 binary inputs and 16 binary
outputs. At BRTN, they were assembled in a
small box, together with a 24 V power supply
unit which is also used to control the indicator
lamps. Three boxes of this type and a fuse
box mounted behind the back of the seat
make up a set of 72 inputs and 48 outputs per
auditorium seating module. Short cables are
then permanently installed in the wall of the
auditorium from the pushbuttons and the
indicator lamps and led to the fieldbus
module.
Each fieldbus module now only requires the fieldbus cable and the extension cable for the power supply to be connected when the seating is installed. It also becomes more convenient on the PC side. An interface card, which is plugged directly onto the ISA bus of the PC, takes the place of a separately programmed PLC. The data is then transferred using a PC program written in C++. The same PC is used for generating the results and displaying them on the screen..
The INTERBUS connection allows
much more interaction from the
audience
Advantages
At the top of the list are the enormous savings
in cable. Recording of a game show like "Vip
Vip Hoera" takes place every few weeks, on
two consecutive days. Thereafter, the studio
set disappears behind the wings again for a
few weeks. The whole thing is electrically
"safer" to assemble and dismantle, since the
cables between the pushbuttons and
INTERBUS are securely mounted on the
auditorium seating. The cabling is limited to
connecting two bus cables and the power
supply cable.
Compared to reconnecting complex cable bundles, this is simpler, operationally safer and more time-saving. Problems with mixed-up cables are out, conductors which are becoming loose are easy to locate. And: after assembly, the pushbuttons do not all have to be tested individually, since wire-break and other anomalies are detected by the modules themselves.
The whole application works with one single PC. The PLC used to
be necessary in parallel cabling as the "mounting panel" for
hundreds of inputs and outputs, and is now superfluous.
The whole thing is far more cost-saving. The modules represent an
investment of 0.5 Mio BEF, a sum which is fast amortized. The
cabling costs are reduced, since shorter cables and less cabling
time are necessary. By means of this unique investment, time and
money can be saved for subsequent studio sets. And one more
advantage: by using INTERBUS, even more complicated
interactions with the audience can be put into practice at a
reasonable budget.
Alfons Calders, Belgium